Nasal lavage natural killer cell function is suppressed in smokers after live attenuated influenza virus

Background

Modified function of immune cells in nasal secretions may play a role in the enhanced susceptibility to respiratory viruses that is seen in smokers. Innate immune cells in nasal secretions have largely been characterized by cellular differentials using morphologic criteria alone, which have successfully identified neutrophils as a significant cell population within nasal lavage fluid (NLF) cells. However, flow cytometry may be a superior method to fully characterize NLF immune cells. We therefore characterized immune cells in NLF by flow cytometry, determined the effects of live attenuated influenza virus (LAIV) on NLF and peripheral blood immune cells, and compared responses in samples obtained from smokers and nonsmokers.

Methods

In a prospective observational study, we characterized immune cells in NLF of nonsmokers at baseline using flow cytometry and immunohistochemistry. Nonsmokers and smokers were inoculated with LAIV on day 0 and serial nasal lavages were collected on days 1-4 and day 9 post-LAIV. LAIV-induced changes of NLF cells were characterized using flow cytometry. Cell-free NLF was analyzed for immune mediators by bioassay. Peripheral blood natural killer (NK) cells from nonsmokers and smokers at baseline were stimulated in vitro with LAIV followed by flow cytometric and mediator analyses.

Results

CD45(+)CD56(-)CD16(+) neutrophils and CD45(+)CD56(+) NK cells comprised median 4.62% (range 0.33-14.52) and 23.27% (18.29-33.97), respectively, of non-squamous NLF cells in nonsmokers at baseline. LAIV did not induce changes in total NK cell or neutrophil percentages in either nonsmokers or smokers. Following LAIV inoculation, CD16(+) NK cell percentages and granzyme B levels increased in nonsmokers, and these effects were suppressed in smokers. LAIV inoculation enhanced expression of activating receptor NKG2D and chemokine receptor CXCR3 on peripheral blood NK cells from both nonsmokers and smokers in vitro but did not induce changes in CD16(+) NK cells or granzyme B activity in either group.

Conclusions

These data are the first to identify NK cells as a major immune cell type in the NLF cell population and demonstrate that mucosal NK cell cytotoxic function is suppressed in smokers following LAIV. Altered NK cell function in smokers suggests a potential mechanism that may enhance susceptibility to respiratory viruses.     

MR angiography of collateral arteries in a hind limb ischemia model: comparison between blood pool agent Gadomer and small contrast agent Gd-DTPA

The objective of this study was to compare the blood pool agent Gadomer with a small contrast agent for the visualization of ultra-small, collateral arteries (diameter<1 mm) with high resolution steady-state MR angiography (SS-MRA) in a rabbit hind limb ischemia model. Ten rabbits underwent unilateral femoral artery ligation. On days 14 and 21, high resolution SS-MRA (voxel size 0.49×0.49×0.50 mm³) was performed on a 3 Tesla clinical system after administration of either Gadomer (dose: 0.10 mmol/kg) or a small contrast agent (gadopentetate dimeglumine (Gd-DTPA), dose: 0.20 mmol/kg). All animals received both contrast agents on separate days. Selective intra-arterial x-ray angiograms (XRAs) were obtained in the ligated limb as a reference. The number of collaterals was counted by two independent observers. Image quality was evaluated with the contrast-to-noise ratio (CNR) in the femoral artery and collateral arteries. CNR for Gadomer was higher in both the femoral artery (Gadomer: 73±5 (mean ± SE); Gd-DTPA: 40±3; p<0.01) and collateral arteries (Gadomer: 18±4; Gd-DTPA: 9±1; p = 0.04). Neither day of acquisition nor contrast agent used influenced the number of identified collateral arteries (p = 0.30 and p = 0.14, respectively). An average of 4.5±1.0 (day 14, mean ± SD) and 5.3±1.2 (day 21) collaterals was found, which was comparable to XRA (5.6±1.7, averaged over days 14 and 21; p>0.10). Inter-observer variation was 24% and 18% for Gadomer and Gd-DTPA, respectively. In conclusion, blood pool agent Gadomer improved vessel conspicuity compared to Gd-DTPA. Steady-state MRA can be considered as an excellent non-invasive alternative to intra-arterial XRA for the visualization of ultra-small collateral arteries.     

Immobilized laccase of Cerrena unicolor for elimination of endocrine disruptor micropollutants

The white-rot fungus Cerrena unicolor C-139 produced 450?000 U l⁻¹ of laccase when cultivated in submerged (50 ml) fermentation of wheat bran. Laccase (benzenediol: oxygen oxidoreductase, EC 1.10.3.2.), from C. unicolor C-139 was immobilized covalently on control porosity carrier silica beads. The activity of the immobilized laccase was approximately 15.8 units per gram of silica beads. The pH optimum was between 2.5 and 3.0 for free and immobilized laccase. The immobilization of enzyme appeared to be the main factor for retention of laccase activity at high temperature of 80 °C. The apparent K_m value (100 μmol) of immobilized laccase from C. unicolor C-139 was 6.7 times higher than free laccase (15 μmol) using 2,2-azino-bis-[3-ethylthiazoline-6-sulfonate] (ABTS) as the substrate. Immobilized laccase was able to eliminate 80 % of Bisphenol A, 40 % of Nonylphenol, and 60 % of Triclosan from solutions containing 50 μmol of each micropollutant separately. The experiments were run three times consecutively with the same immobilized laccase without loss of enzyme activity.     

S-emopamil ameliorates ischemic brain damage in rats: histological and behavioural approaches

Transient ischemia induced by 4 vessel occlusion (4VO) in rats is known to produce neuronal damage to particular brain structures such as the CA1 sector of the hippocampus. Behavioural changes associated with ischemic lesioning of this brain region are an impairment in spatial learning of rats tested in a water maze (14). In the present study, it was investigated whether pretreatment with S-emopamil, a Ca2(+)-channel blocker as well as a 5-HT2 antagonist, prevents the occurrence of hippocampal cell damage and/or spatial learning impairments in rats subjected to 4VO. Neuronal lesioning in the hippocampus was significantly reduced following pretreatment with S-emopamil in 4VO rats. In addition, S-emopamil treated animals showed an improved spatial learning ability compared to saline treated 4VO rats. It is suggested that S-emopamil may exert a protective effect under ischemic conditions. The possible mechanisms involved are discussed.     

An MRI study on the relations between muscle atrophy, shoulder function and glenohumeral deformity in shoulders of children with obstetric brachial plexus injury

Objective

it has been established that chronic neck pain following whiplash is associated with the phenomenon of central sensitization, in which injured and uninjured parts of the body exhibit lowered pain thresholds due to an alteration in central pain processing. it has furthermore been hypothesized that peripheral sources of nociception in the muscles may perpetuate central sensitization in chronic whiplash. the hypothesis explored in the present study was whether myofascial trigger points serve as a modulator of central sensitization in subjects with chronic neck pain.

Design

controlled case series.

Setting

outpatient chronic pain clinic.

Subjects

seventeen patients with chronic and intractable neck pain and 10 healthy controls without complaints of neck pain.

Intervention

symptomatic subjects received anesthetic infiltration of myofascial trigger points in the upper trapezius muscles and controls received the anesthetic in the thigh. Outcome measures: pre and post injection cervical range of motion, pressure pain thresholds (ppt) over the infraspinatus, wrist extensor, and tibialis anterior muscles. sensitivity to light (photophobia) and subjects' perception of pain using a visual analog scale (vas) were also evaluated before and after injections. only the ppt was evaluated in the asymptomatic controls.

Results

immediate (within 1 minute) alterations in cervical range of motion and pressure pain thresholds were observed following an average of 3.8 injections with 1–2 cc of 1% lidocaine into carefully identified trigger points. cervical range of motion increased by an average of 49% (p = 0.000) in flexion and 44% (p = 0.001) in extension, 47% (p = 0.000) and 28% (p < 0.016) in right and left lateral flexion, and a 27% (p = 0.002) and 45% (p = 0.000) in right and left rotation. ppt were found increased by 68% over the infraspinatus (p = 0.000), by 78% over the wrist extensors (p = 0.000), and by 64% over the tibialis anterior (p = 0.002). among 11 subjects with photophobia, only 2 remained sensitive to light after the trigger point injections (p = 0.033). average vas dropped by 57%, from 6.1 to 2.6 (p = 0.000). no significant changes in ppt were observed in the control group following lidocaine infiltration of the thigh.

Conclusion

the present data suggest that myofascial trigger points serve to perpetuate lowered pain thresholds in uninjured tissues. additionally, it appears that lowered pain thresholds associated with central sensitization can be immediately reversed, even when associated with long standing chronic neck pain. although the effects resulting from anesthesia of trigger points in the present study were temporary, it is possible that surgical excision or ablation of the same trigger points may offer more permanent solutions for chronic neck pain patients. further study is needed to evaluate these and other options for such patients.     

Illuminating the detection chain of bacterial bioreporters

Engineering bacteria for measuring chemicals of environmental or toxicological concern (bioreporter bacteria) has grown slowly into a mature research area. Despite many potential advantages, current bioreporters do not perform well enough to comply with environmental detection standards. Basically, the reasons for this are the lack of engineering principles in the detection chain in the bioreporters. Here, we dissect critical steps in the detection chain and illustrate how bioreporter design could be improved by mutagenizing specificity and selectivity of the sensing and regulatory proteins, by newer expression strategies and application of different signalling networks. Furthermore, we describe how redesigning bioreporter assays with respect to pollutant transport into the cells and application of other detection devices can decrease detection limits and increase the speed of detection.     

Interleukins 19, 20, and 24 signal through two distinct receptor complexes. Differences in receptor-ligand interactions mediate unique biological functions

Cytokines that signal through Class II receptors form a distinct family that includes the interferons and interleukin 10 (IL-10). Recent identification of several IL-10 homologs has defined a cytokine subfamily that includes AK155, IL-19, IL-20, IL-22, and IL-24. Within this subfamily, IL-19, IL-20, and IL-24 exhibit substantial sharing of receptor complexes; all three are capable of signaling through IL-20RA/IL-20RB, and IL-20 and IL-24 both can also use IL-22R/IL-20RB. However, the biological effects of these three cytokines appear quite distinct: immune activity with IL-19, skin biology with IL-20, and tumor apoptosis with IL-24. To more fully elucidate their interactions with the receptor complexes, we have performed a series of in vitro assays. Reporter, proliferation, and direct STAT activation assays using cell lines expressing transfected receptors revealed differences between the receptor complexes. IL-19 and IL-24 also exhibited growth inhibition on a cell line endogenously expressing all three receptor subunits, an effect that was seen at cytokine levels two orders of magnitude above those required for STAT activation or proliferation. These results demonstrate that, although this subclass exhibits receptor complex redundancy, there are differences in ligand/receptor interactions and in signal transduction that may lead to specificity and a distinct biology for each cytokine.     

Properties of Streptomyces sp. endo-β-xylanases in relation to their applicability in kraft pulp bleaching

A screening of a collection of Streptomyces sp. strains has shown that Streptomyces achromogenes 5028 (S1), Streptomyces longisporus ruber 4–167 (S2) and Streptomyces sp. 8812 (S3) degraded efficiently beechwood xylan. The -xylanase activities present in the culture filtrate of the strains were purified to electrophoretic homogeneity and found to be typical non-debranching endo--xylanases (1,4--D-xylan xylanohydrolases: E.C. 3.2.1.8) with respective molecular weights of 25,000 (S1), 45,000 (S2) and 22,000 (S3). The enzymes were characterized with respect to their temperature–pH relationship and kinetic profile. Immunological experiments suggested that the enzyme produced by S1 belonged to family 11 of glycanases and the S3 enzyme to family 10. The three xylanases adsorbed onto crystalline cellulose but were catalytically inert towards this material, indicating a possible application of these enzymes in biobleaching processes. With respect to its effect on and brightness values in a DEDED bleaching sequence, the xylanase produced by the S1 strain appeared as comparable to a Trichoderma longibrachiatum commercial enzyme preparation (Novozym 431). Streptomyces sp. xylanases may find applications in elemental-chlorine-free bleaching procedures.     

Arabidopsis RADICAL-INDUCED CELL DEATH1 belongs to the WWE protein-protein interaction domain protein family and modulates abscisic acid, ethylene, and methyl jasmonate responses

Experiments with several Arabidopsis thaliana mutants have revealed a web of interactions between hormonal signaling. Here, we show that the Arabidopsis mutant radical-induced cell death1 (rcd1), although hypersensitive to apoplastic superoxide and ozone, is more resistant to chloroplastic superoxide formation, exhibits reduced sensitivity to abscisic acid, ethylene, and methyl jasmonate, and has altered expression of several hormonally regulated genes. Furthermore, rcd1 has higher stomatal conductance than the wild type. The rcd1-1 mutation was mapped to the gene At1g32230 where it disrupts an intron splice site resulting in a truncated protein. RCD1 belongs to the (ADP-ribosyl)transferase domain-containing subfamily of the WWE protein-protein interaction domain protein family. The results suggest that RCD1 could act as an integrative node in hormonal signaling and in the regulation of several stress-responsive genes.