Orbital shaking conditions augment human nasoseptal cartilage formation in 3D culture.

Introduction: This study aimed to determine whether a dynamic orbital shaking culture system could enhance the cartilage production and viability of bioengineered nasoseptal cartilage. Methods: Human nasal chondrocytes were seeded onto nanocellulose-alginate biomaterials and cultured in static or dynamic conditions for 14 days. Quantitative polymerase chain reaction for chondrogenic gene expression (type 2 collagen, aggrecan and SOX9) was performed, demonstrating a transient rise in SOX9 expression at 1 and 7 days of culture, followed by a rise at 7 and 14 days in Aggrecan (184.5-fold increase, p < 0.0001) and Type 2 Collagen (226.3-fold increase, p = 0.049) expression. Samples were analysed histologically for glycosaminoglycan content using Alcian blue staining and demonstrated increased matrix formation in dynamic culture. Results: Superior cell viability was identified in the dynamic conditions through live-dead and alamarBlue assays. Computational analysis was used to determine the shear stress experienced by cells in the biomaterial in the dynamic conditions and found that the mechanical stimulation exerted was minimal (fluid shear stress <0.02 mPa, fluid pressure <48 Pa). Conclusion: We conclude that the use of an orbital shaking system exerts biologically relevant effects on bioengineered nasoseptal cartilage independently of the expected thresholds of mechanical stimulation, with implications for optimising future cartilage tissue engineering efforts.

The Occupational and Environmental Hazards of Uncovered Toilets.

ABSTRACT: Substantial evidence demonstrates that plumes from uncovered toilets potentially expose nurses and other health care workers to aerosols containing infectious agents and hazardous drugs, including antineoplastic drugs. Most hospitals in the United States utilize flushometer-type toilets, which operate under high pressure and do not have a permanently attached closure or lid, which is known to reduce the aerosols generated by flushing. This article aims to raise awareness among nurses of the potential exposure risks associated with toilet plume aerosols, so they can educate other health care workers and take part in initiatives to address these risks.

Multiscale QM/MM modelling of catalytic systems with ChemShell.

Hybrid quantum mechanical/molecular mechanical (QM/MM) methods are a powerful computational tool for the investigation of all forms of catalysis, as they allow for an accurate description of reactions occurring at catalytic sites in the context of a complicated electrostatic environment. The scriptable computational chemistry environment ChemShell is a leading software package for QM/MM calculations, providing a flexible, high performance framework for modelling both biomolecular and materials catalysis. We present an overview of recent applications of ChemShell to problems in catalysis and review new functionality introduced into the redeveloped Python-based version of ChemShell to support catalytic modelling. These include a fully guided workflow for biomolecular QM/MM modelling, starting from an experimental structure, a periodic QM/MM embedding scheme to support modelling of metallic materials, and a comprehensive set of tutorials for biomolecular and materials modelling.

Contribution of histological, serological, and genetic factors to the clinical heterogeneity of adult-onset coeliac disease.

OBJECTIVE: Although the factors predisposing to coeliac disease (CD) are largely understood, it remains unclear what determines the clinical heterogeneity of the disease. The aim of this study was to explore the contribution of histological, serological, and genetic factors to disease presentation. MATERIAL AND METHODS: The study was designed as a retrospective chart review of 384 unrelated Caucasian patients diagnosed with CD after the age of 16 at a single UK centre. RESULTS: We found that 8.8% of IgA-competent CD patients were endomysial antibody (EMA)-negative. Compared with the EMA-positive group, EMA-negative CD patients had a lower prevalence of iron deficiency (52.0% versus 72.6%, p=0.03) and Marsh IIIb-c lesions (66.7% versus 85.3%, p=0.03). Histological severity at diagnosis correlated with anaemia (p<0.01), folate deficiency (p<0.01), and iron deficiency (p=0.05), but no other laboratory or clinical features. Compared with human leucocyte antigen (HLA)-DQ2.5-positive patients, those carrying HLA-DQ2.2 were similar in terms of all the characteristics we considered, whereas those carrying HLA-DQ8 had a lower frequency of EMA positivity (62.5% versus 92.6%, p<0.01). The proportion of EMA-positive patients increased with frequency of the HLA-DQB1*0201 allele (76.7% versus 92.3% versus 96.4% for 0 versus 1 versus 2 alleles, p<0.01); no other evidence of a gene-dose effect of HLA-DQB1*0201 was observed. CONCLUSIONS: Histological severity at diagnosis of CD is associated with anaemia and some micronutrient deficiencies, but no other clinical features. The proportion of EMA-positive patients is higher amongst those carrying HLA-DQ2 than in those carrying HLA-DQ8, and is highest in HLA-DQ2 homozygotes. We found no correlation between frequency of the HLA-DQ alleles encoding HLA-DQ2.5 and CD severity.

Pneumococcal infection in patients with coeliac disease.

OBJECTIVES: Some patients with coeliac disease are hyposplenic. Splenectomy is a risk factor for pneumococcal infection. Our objective was to determine the risk of invasive pneumococcal disease - septicaemia, pneumonia or meningitis - in patients with coeliac disease. METHODS: We analysed routinely collected, linked statistical records of hospital admission to study the risk of pneumococcal infection in patients with coeliac disease, in patients who underwent splenectomy and in a comparison cohort. The main outcome measure was the rate ratio for pneumococcal infection in the coeliac and splenectomized cohorts, compared with the comparison cohort. We undertook the study using linked records in two temporally and geographically distinct populations: the Oxford region (1963-1999) and the whole of England (1998-2003). RESULTS: The rate ratio of pneumococcal infection in patients with coeliac disease was 2.06 (95% confidence interval, 1.27-3.15) in the Oxford population and 1.61 (1.36-1.90) in England as a whole. As a comparison, the rate ratios in splenectomized patients were 3.40 (2.44-4.60) and 3.32 (2.80-3.90) in the Oxford and England populations, respectively. The increased rate ratio in coeliac patients persisted beyond the first year after diagnosis of the coeliac disease. The period covered by the Oxford study was mainly before the widespread availability of pneumococcal vaccination; but the availability of pneumococcal vaccine was widespread during the time of the English study. CONCLUSION: Some patients with coeliac disease have an elevated risk of invasive pneumococcal disease.

The Federal Emergency Management Agency joins hands with the American Society of Civil Engineers to promote flood hazard mitigation

The American Society of Civil Engineers (ASCE) has made a major commitment to flood hazard mitigation over the past several years. This commitment has resulted in a developing close working relationship with the Federal Emergency Management Agency (FEMA). Two major developments have resulted from this collaborative effort. The ASCE-7 Standard, "Minimum Design Loads for Buildings and Other Structures", is being revised to include flood loads, and a new ASCE Standard, "Flood Resistant Design and Construction for Buildings and Other Structures," is being completed. Both standards will include mandatory language suitable for code adoption and non-mandatory commentary portions