Secondhand smoke alters arachidonic acid metabolism and inflammation in infants and children with cystic fibrosis

BACKGROUND

Mechanisms that facilitate early infection and inflammation in cystic fibrosis (CF) are unclear. We previously demonstrated that children with CF and parental-reported secondhand smoke exposure (SHSe) have increased susceptibility to bacterial infections. SHSe hinders arachidonic acid (AA) metabolites that mediate immune function in patients without CF, and may influence CF immune dysfunction. We aimed to define SHSe's impact on inflammation mediators and infection in children with CF.

METHODS

Seventy-seven children with CF <10 years of age (35 infants <1 year; 42 children 1-10 years) were enrolled and hair nicotine concentrations measured as an objective surrogate of SHSe. AA signalling by serum and macrophage lipidomics, inflammation using blood transcriptional profiles and in vitro macrophage responses to bacterial infection after SHSe were assessed.

RESULTS

Hair nicotine concentrations were elevated in 63% of patients. Of the AA metabolites measured by plasma lipidomics, prostaglandin D₂ (PGD₂) concentrations were decreased in children with CF exposed to SHSe, and associated with more frequent hospitalisations (p=0.007) and worsened weight z scores (p=0.008). Children with CF exposed to SHSe demonstrated decreased expression of the prostaglandin genes PTGES3 and PTGR2 and overexpression of inflammatory pathways. These findings were confirmed using an in vitro model, where SHSe was associated with a dose-dependent decrease in PGD₂ and increased methicillin-resistant Staphylococcus aureus survival in human CF macrophages.

CONCLUSIONS

Infants and young children with CF and SHSe have altered AA metabolism and dysregulated inflammatory gene expression resulting in impaired bacterial clearance. Our findings identified potential therapeutic targets to halt early disease progression associated with SHSe in the young population with CF.

Insight into Human Resources for Health Status in Nepal

DOI: http://dx.doi.org/10.3126/hprospect.v11i0.7431 Health Prospect 2012;11:40-41

The expression of Mirc1/Mir17-92 cluster in sputum samples correlates with pulmonary exacerbations in cystic fibrosis patients

INTRODUCTION

Cystic fibrosis (CF) is a multi-organ disorder characterized by chronic sino-pulmonary infections and inflammation. Many patients with CF suffer from repeated pulmonary exacerbations that are predictors of worsened long-term morbidity and mortality. There are no reliable markers that associate with the onset or progression of an exacerbation or pulmonary deterioration. Previously, we found that the Mirc1/Mir17-92a cluster which is comprised of 6 microRNAs (Mirs) is highly expressed in CF mice and negatively regulates autophagy which in turn improves CF transmembrane conductance regulator (CFTR) function. Therefore, here we sought to examine the expression of individual Mirs within the Mirc1/Mir17-92 cluster in human cells and biological fluids and determine their role as biomarkers of pulmonary exacerbations and response to treatment.

METHODS

Mirc1/Mir17-92 cluster expression was measured in human CF and non-CF plasma, blood-derived neutrophils, and sputum samples. Values were correlated with pulmonary function, exacerbations and use of CFTR modulators.

RESULTS

Mirc1/Mir17-92 cluster expression was not significantly elevated in CF neutrophils nor plasma when compared to the non-CF cohort. Cluster expression in CF sputum was significantly higher than its expression in plasma. Elevated CF sputum Mirc1/Mir17-92 cluster expression positively correlated with pulmonary exacerbations and negatively correlated with lung function. Patients with CF undergoing treatment with the CFTR modulator Ivacaftor/Lumacaftor did not demonstrate significant change in the expression Mirc1/Mir17-92 cluster after six months of treatment.

CONCLUSIONS

Mirc1/Mir17-92 cluster expression is a promising biomarker of respiratory status in patients with CF including pulmonary exacerbation.

In serum, higher parathyroid hormone but not lower vitamin D is associated with oral squamous cell carcinoma

INTRODUCTION

Vitamin D and calcium are known to regulate differentiation and proliferation of keratinocytes; they might potentially have a role in suppressing carcinogenesis in squamous epithelium. Serum parathyroid hormone (pth) is a sensitive indicator of calcium and vitamin D deficiency, and 25-hydroxyvitamin D [25(OH)D] is an established marker of vitamin D status.

METHODS

To determine whether levels of 25(OH)D, calcium, or pth in serum are associated with oral squamous cell carcinoma (oscc), we examined those parameters in serum collected from 70 patients with oscc and from an equal number of matched control subjects.

RESULTS

The results showed that intact pth was significantly higher in serum from oscc patients than in serum from control subjects. However, we observed no significant differences in 25(OH)D or calcium in serum from oscc patients and from control subjects.

CONCLUSIONS

We conclude that higher serum pth, but not lower serum vitamin D or calcium, is associated with oscc.

Activation of conventional kinesin motors in clusters by Shaw voltage-gated K+ channels

The conventional kinesin motor transports many different cargos to specific locations in neurons. How cargos regulate motor function remains unclear. Here we focus on KIF5, the heavy chain of conventional kinesin, and report that the Kv3 (Shaw) voltage-gated K(+) channel, the only known tetrameric KIF5-binding protein, clusters and activates KIF5 motors during axonal transport. Endogenous KIF5 often forms clusters along axons, suggesting a potential role of KIF5-binding proteins. Our biochemical assays reveal that the high-affinity multimeric binding between the Kv3.1 T1 domain and KIF5B requires three basic residues in the KIF5B tail. Kv3.1 T1 competes with the motor domain and microtubules, but not with kinesin light chain 1 (KLC1), for binding to the KIF5B tail. Live-cell imaging assays show that four KIF5-binding proteins, Kv3.1, KLC1 and two synaptic proteins SNAP25 and VAMP2, differ in how they regulate KIF5B distribution. Only Kv3.1 markedly increases the frequency and number of KIF5B-YFP anterograde puncta. Deletion of Kv3.1 channels reduces KIF5 clusters in mouse cerebellar neurons. Therefore, clustering and activation of KIF5 motors by Kv3 regulate the motor number in carrier vesicles containing the channel proteins, contributing not only to the specificity of Kv3 channel transport, but also to the cargo-mediated regulation of motor function.

Branch retinal arterial occlusion

Retinal arterial occlusion is an ocular emergency in which visual prognosis is poor mostly due to late presentation of the patient and macular involvement. The casee described, in this report is ane incidence of Branch Retinal Arterial Occlusion in a 22 year old female with grade II Mitral Regurgitation. The patiente presented witha complaint of painless, diminution of vision in the right eyn. She also presented with perception of black shadow in the superior visual fiel n of the same eye5 for five days. There was no significant systemic ord personal history. Her visual acuity at presentation was 6/60 and 6/6 in the right and left eyes,y which did not improve with glasses or pin-hole. Anterior segment including papillary reaction was normal in both eyes while Fundus examination of the right eye revealed retinal whitening inside the inferotemporal vascular arcade that was encroaching foveolar avascular zone. Visual field defect was detected at superonasally inside arhade but Fundus Fluorescence Angiography was normal. An echoycardiograph revealed grade II Mitral Regurgitation. The patient was kept on observation and after two2 days of follow-up, vision in the right eye was improved to 6/6 unaided but visual field defect was remained same.

Inadequate hospital reimbursement for victims of motor vehicle crashes due to health reform legislation

STUDY OBJECTIVE

Effective for 1997, health reform legislation in New York resulted in a change in hospital reimbursement for victims of motor vehicle crashes. We evaluated the impact of this change from no-fault to Medicaid rates on the financial viability of a regional trauma center within an academic medical center.

METHODS

This study represents a retrospective review of the trauma registry for all motor vehicle-related injuries (meeting the statewide definition of trauma) admitted to a regional trauma center for a 9-month period just before the legislation implementation date. Charges, costs, and projected reimbursement were calculated by standard hospital accounting methods. Profit or loss (reimbursement minus costs) was calculated by standard hospital accounting methods for each admission using no-fault and Medicaid reimbursement rates.

RESULTS

One hundred seventy-three cases during the 9-month period generated total charges of $4,112,174, total costs of $3,447,110, and estimated total profit of $800,084 ($4,625 per case) using no-fault reimbursement and a total loss of $184,154 ($1,064 per case) using Medicaid reimbursement. For the 31 patients with diagnosis-related groups (DRGs) that were specifically created in New York to ensure adequate reimbursement for multiple significant trauma (730 through 734 and 792 through 794), no-fault reimbursement resulted in an average profit of $371 per case and Medicaid generated a loss of $6,118 per case. Actual payments for the study population were almost $500,000 less than estimated.

CONCLUSION

Changes in rates of no-fault insurance payments to hospitals will result in inadequate reimbursement for motor vehicle crash victims admitted to a regional trauma center, undermining the viability of the regional trauma system.