Dynamics of history-dependent perceptual judgment.

Identical physical inputs do not always evoke identical percepts. To investigate the role of stimulus history in tactile perception, we designed a task in which rats had to judge each vibrissal vibration, in a long series, as strong or weak depending on its mean speed. After a low-speed stimulus (trial n - 1), rats were more likely to report the next stimulus (trial n) as strong, and after a high-speed stimulus, they were more likely to report the next stimulus as weak, a repulsive effect that did not depend on choice or reward on trial n - 1. This effect could be tracked over several preceding trials (i.e., n - 2 and earlier) and was characterized by an exponential decay function, reflecting a trial-by-trial incorporation of sensory history. Surprisingly, the influence of trial n - 1 strengthened as the time interval between n - 1 and n grew. Human subjects receiving fingertip vibrations showed these same key findings. We are able to account for the repulsive stimulus history effect, and its detailed time scale, through a single-parameter model, wherein each new stimulus gradually updates the subject's decision criterion. This model points to mechanisms underlying how the past affects the ongoing subjective experience.

Long-Term Venovenous Connection for Extracorporeal Carbon Dioxide Removal (ECCO2R)-Numerical Investigation of the Connection to the Common Iliac Veins.

PURPOSE: Currently used cannulae for extracorporeal carbon dioxide removal (ECCO2R) are associated with complications such as thrombosis and distal limb ischemia, especially for long-term use. We hypothesize that the risk of these complications is reducible by attaching hemodynamically optimized grafts to the patient's vessels. In this study, as a first step towards a long-term stable ECCO2R connection, we investigated the feasibility of a venovenous connection to the common iliac veins. To ensure its applicability, the drainage of reinfused blood (recirculation) and high wall shear stress (WSS) must be avoided. METHODS: A reference model was selected for computational fluid dynamics, on the basis of the analysis of imaging data. Initially, a sensitivity analysis regarding recirculation was conducted using as variables: blood flow, the distance of drainage and return to the iliocaval junction, as well as the diameter and position of the grafts. Subsequently, the connection was optimized regarding recirculation and the WSS was evaluated. We validated the simulations in a silicone model traversed by dyed fluid. RESULTS: The simulations were in good agreement with the validation measurements (mean deviation 1.64%). The recirculation ranged from 32.1 to 0%. The maximum WSS did not exceed 5.57 Pa. The position and diameter of the return graft show the highest influence on recirculation. A correlation was ascertained between recirculation and WSS. Overall, an inflow jet directed at a vessel wall entails not only high WSS, but also a flow separation and thereby an increased recirculation. Therefore, return grafts aligned to the vena cava are crucial. CONCLUSION: In conclusion, a connection without recirculation could be feasible and therefore provides a promising option for a long-term ECCO2R connection.

Impact of epicardial adipose tissue volume upon left ventricular dysfunction in patients with mild-to-moderate aortic stenosis: A post-hoc analysis.

BACKGROUND: Aortic stenosis (AS) may lead to diastolic dysfunction and later on heart failure (HF) with preserved left ventricular ejection fraction (HFpEF) via increased afterload and left-ventricular (LV) hypertrophy. Since epicardial adipose tissue (EAT) is a metabolically active fat depot that is adjacent to the myocardium and can influence cardiomyocytes and LV function via secretion of proinflammatory cytokines, we hypothesized that high amounts of EAT, as assessed by computed tomography (CT), may aggravate the development and severity of LV hypertrophy and diastolic dysfunction in the context of AS. METHODS: We studied 50 patients (mean age 71 ± 9 years; 9 women) in this preliminary study with mild or moderate AS and mild to severe LV diastolic dysfunction (LVDD), diagnosed by echocardiography, who underwent non-contrast cardiac CT and echocardiography. EAT parameters were measured on 2nd generation dual source CT. Conventional two-dimensional echocardiography and Tissue Doppler Imaging (TDI) was performed to assess LV function and to derive myocardial straining parameter. All patients had a preserved LV ejection fraction > 50%. Data was analysed using Pearson's correlation. RESULTS: Only weak correlation was found between EAT volume or density and E/é ratio as LVDD marker (r = -.113 p = .433 and r = .260, p = .068 respectively). Also, EAT volume or density were independent from Global Strain Parameters (r = 0.058 p = .688 and r = -0.207 p = .239). E/é ratio was strongly associated with LVDD (r = .761 p≤0.0001) and Strain Parameters were moderately associated with LV Ejection Fraction (r = -.669 p≤0.001 and r = -.454 P≤0.005). CONCLUSIONS: In this preliminary study in patients with AS, the EAT volume and density as assessed by CT correlated only weakly with LVDD, as expressed by the commonly used E/é ratio, and with LV strain function. Hence, measuring EAT volume and density may neither contribute to the prediction nor upon the severity of LVDD, respectively.

Short communication: Lethal mutations in Vorderwald cattle through Montbéliarde incrossings.

Vorderwald cattle are a dual-purpose cattle breed with high migrant contributions from Montbéliarde bulls in the recent past. Through the wide use of Montbéliarde bulls, undesirable alleles were also disseminated into the Vorderwald population. Haplotypes on bovine chromosome 19 (MH1) and 29 (MH2), supposed to harbor lethal mutations, were identified in Montbéliarde cattle. A study in French Montbéliarde cattle identified the PFAS:g.28511199C>T (rs455876205) variant as the most likely MH1 embryonic lethal mutation. The objective of the present study was to determine whether the PFAS:g.28511199C>T variant was introduced into Vorderwald cattle through Montbéliarde bulls and disseminated in this population. The present study expands on previous work on the deleterious SLC37A2 variant (ss2019324563) of the MH2 locus. Herein, we traced the ss2019324563 variant back to the Montbéliarde bull, which was the most likely source for this deleterious mutation in Vorderwald cattle. We genotyped 354 Vorderwald cattle for the PFAS variant, resulting in 41 heterozygous individuals and a T allele frequency of 0.058. An aborted fetus homozygous mutant for SLC37A2 from our previous study on the MH2 locus in Vorderwald cattle was wild type for the PFAS variant. Both lethal mutations were segregating independently of each other, and we found no indications of joint occurrence in a larger number of animals. Neither SLC37A2 nor PFAS double heterozygous mutants were lethal. The earliest animal with a heterozygous PFAS genotype was 1 of 5 migrant Montbéliarde bulls, and this bull was the most likely origin of the deleterious PFAS allele in Vorderwald cattle. All Vorderwald cattle under study born before introgression of this Montbéliarde bull were homozygous wild type. In addition, all 41 heterozygous Vorderwald cattle had genetic contributions from this Montbéliarde bull, whereas in 74 Vorderwald cattle without genes from Montbéliarde bulls, the PFAS T allele was not observed. In a sample of actual German Fleckvieh the PFAS T allele could be found at a very low frequency. Our study demonstrated the introgression of lethal variants through Montbéliarde bulls into a traditional cattle breed highly adapted to harsh local conditions. These findings underline the need to screen bulls for lethal mutations before their wide use in breeding, particularly in breeds with a focus on preservation of their genetic uniqueness.

Breeding experiments and genome-wide association analysis elucidate two genetically different forms of non-syndromic congenital cleft lip and jaw in Vorderwald × Montbéliarde cattle.

Non-syndromic congenital cleft lip and jaw (CLJ) is a condition reported in Vorderwald × Montbéliarde cattle. The objective of the present study was to perform a genome-wide association study (GWAS) for 10 CLJ-affected and 50 unaffected Vorderwald × Montbéliarde cattle using the bovine Illumina high density bead chip to identify loci for this condition. Phenotypic classification of CLJ was based on a detailed recording of orofacial structures using computed tomography. A breeding experiment among CLJ-affected Vorderwald × Montbéliarde cattle and CLJ-affected Vorderwald × Montbéliarde cattle with unaffected Holsteins confirmed recessive inheritance and different loci for bilateral or left-sided versus right-sided CLJ. The GWAS for the five cases with right-sided CLJ gave a genome-wide signal on bovine chromosome (BTA) 29 at 16 Mb. For the four left-sided and one bilateral CLJ case, a genome-wide significant association was identified on BTA4 at 32 Mb. Two different loci are very likely to be involved in CLJ in Vorderwald × Montbéliarde cattle because experimental matings among affected cows and bulls with different types of CLJ did not result in CLJ-affected progeny, and in addition, two different loci were also found through GWAS and mapped on two different bovine chromosomes. Validation in 346 Vorderwald × Montbéliarde cattle for the highly associated SNPs on BTA4 and 29 gave ratios of 33/346 (0.095, BTA4) and 6/346 (0.017, BTA29) homozygous mutant genotypes. Further studies should elucidate the responsible mutations underlying the different types of CLJ in Vorderwald × Montbéliarde cattle.

Expression profiling and functional analysis of Toll-like receptors in primary healthy human nasal epithelial cells shows no correlation and a refractory LPS response.

BACKGROUND: Innate immune recognition via Toll-like receptors (TLRs) on barrier cells like epithelial cells has been shown to influence the regulation of local immune responses. Here we determine expression level variations and functionality of TLRs in nasal epithelial cells from healthy donors. METHODS: Expression levels of the different TLRs on primary nasal epithelial cells from healthy donors derived from inferior turbinates was determined by RT-PCR. Functionality of the TLRs was determined by stimulation with the respective ligand and evaluation of released mediators by Luminex ELISA. RESULTS: Primary nasal epithelial cells express different levels of TLR1-6 and TLR9. We were unable to detect mRNA of TLR7, TLR8 and TLR10. Stimulation with Poly(I:C) resulted in a significant increased secretion of IL-4, IL-6, RANTES, IP-10, MIP-1ß, VEGF, FGF, IL-1RA, IL-2R and G-CSF. Stimulation with PGN only resulted in significant increased production of IL-6, VEGF and IL-1RA. Although the expression of TLR4 and co-stimulatory molecules could be confirmed, primary nasal epithelial cells appeared to be unresponsive to stimulation with LPS. Furthermore, we observed huge individual differences in TLR agonist-induced mediator release, which did not correlate with the respective expression of TLRs. CONCLUSION: Our data suggest that nasal epithelium seems to have developed a delicate system of discrimination and recognition of microbial patterns. Hypo-responsiveness to LPS could provide a mechanism to dampen the inflammatory response in the nasal mucosa in order to avoid a chronic inflammatory response. Individual, differential expression of TLRs on epithelial cells and functionality in terms of released mediators might be a crucial factor in explaining why some people develop allergies to common inhaled antigens, and others do not.

Endoscopic treatment of inverted papilloma attached in the frontal sinus/recess.

BACKGROUND: Inverted papilloma (IP) is a benign sinonasal tumour for which endoscopic surgery, with complete removal of the underlying and surrounding mucoperiosteum at the attachment site followed by drilling and/or coagulation of this area, is the treatment of choice. This can be challenging in the frontal sinus. OBJECTIVES: To report on the outcome of treatment for IPs involving the frontal sinus. To propose the possible use of topical 5-fluorouracil 5% (5-FU) in the postoperative management of challenging IPs. METHODS: This is a retrospective cohort evaluation of patients with IPs attached in the frontal sinus or in the frontal recess and growing into the frontal sinus. Data on primary or revision surgery, uni- or bilaterality, attachment site, surgical procedure, 5-FU usage, recurrence and follow-up are provided. The end points are disease-free follow-up in months and recurrence. RESULTS: Twenty cases, including fifteen revision cases, were retrieved over a period of ten years. All cases were treated endoscopically. Two cases recurred (10%) and the intervention was repeated. In eight cases, 5-FU was applied at the end of surgery. None of these cases recurred. The mean follow-up after the last intervention was 42 months (standard deviation (SD) 22.1). CONCLUSION: IP involving the frontal sinus is a surgical challenge that can be successfully addressed endoscopically. The topical application of 5-FU could have a place in postoperative treatment when it is difficult to be absolutely sure that all diseased mucoperichondrium or mucoperiosteum at the attachment site(s) has been completely removed.

Mono-allergic and poly-allergic rhinitis patients have comparable numbers of mucosal Foxp3+CD4+ T lymphocytes.

BACKGROUND: We previously found that allergic rhinitis patients with an isolated pollen sensitization responded more strongly to a nasal provocation with grass pollen (GP) than patients who had an additional house dust mite (HDM) sensitization. To elucidate this phenomenon, we investigated the dynamics of Foxp3+CD4+ T lymphocytes in allergic rhinitis patients with distinct allergen sensitizations. METHODS: Three groups of allergic rhinitis patients with skin prick test confirmed allergic sensitizations were investigated and compared to 14 healthy controls: 14 subjects with an isolated grass pollen sensitization (Mono-GP); 9 subjects with isolated housedust mite sensitization (Mono-HDM); 29 subjects with grass pollen and house dust mite sensitization (poly-sensitized). Subjects in the Mono-GP group were challenged with grass pollen extract, subjects in the Mono-HDM group were challenged with house dust mite extract, subjects in the poly-sensitized group and the healthy controls were randomly challenged with either grass pollen or house dust mite. Nasal biopsies were taken before and after nasal provocation. We compared the distribution of FoxP3+CD4+ cells in nasal biopsies before and after nasal provocation using immunohistochemistry. RESULTS: There was no difference in the number of FoxP3+CD4+ cells between healthy and the three allergic groups at baseline.Nasal provocation did result in an increase in eosinophils in the three allergic groups, but did not result in a change in the number of FoxP3+CD4+ cells in any of the groups or induced differences between any of the groups. CONCLUSION: Clinical differences in the response between mono-GP and multiple-sensitized allergic individuals are not related to differences in the number of regulatory T cells in the nasal mucosa.

Initial experiences with endoscopic rhino-neurosurgery in Amsterdam.

Endoscopic surgery of the skull base has been on the rise for several years. Endoscopic access for surgery can be achieved from the frontal sinus anteriorly along the skull base to the odontoid process posterior inferiorly. An endoscope is inserted through one nasal corridor and allows visualization of the working field and up to three surgical instruments can be used to address the lesion. This is called the "two nostrils-four hands technique". This is a retrospective study of 67 cases. Setting of the study is an Amsterdam University hospital. Cases were identified in the department of otorhinolaryngology and department of neurosurgery database. All patients operated between 1 January, 2008 and 1 February, 2012 with pituitary tumours that extend beyond the sella, sinonasal tumours and all non-pituitary skull-base tumours were included. Mean tumour diameter was 3.8 cm. We performed a near-to-gross total resection in 92% of cases where we intended to perform a total resection. The most frequent complication was CSF leakage. This study demonstrates that this technique is safe and reliable. What is needed is a dedicated team, which includes a dedicated anesthesiologist, endocrinologist, ophthalmologist, and radiation oncologist.

Acute sinusitis and blindness as the first presentation of chronic lymphocytic leukaemia.

Chronic lymphocytic leukaemia (CLL) is the most frequent form of leukaemia among adults in the Western world, presenting at a median age of 65 years. The diagnosis is usually made incidentally during routine blood examination while the disease is still in its early phase. We report a case of blindness of 24 hours due to acute sinusitis based on CLL localisation in a patient with undiagnosed CLL. Emergency endoscopic sinus surgery and intra- and extra-ocular orbital decompression were performed. The sinusitis resolved after surgery and intravenous antibiotics. Her vision improved within 24 hours and eventually recovered completely after six months. Her CLL remained in an indolent state, needing no active treatment. This case illustrates that blindness from a lymphoproliferative disorder may be treated with emergency endoscopic sinus surgery instead of conventional chemotherapy in order to salvage the vision first, even if the vision is lost for more than 24 hours.

Long-term results of functional endoscopic sinus surgery in children with chronic rhinosinusitis with nasal polyps.

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is rare in children and has a major impact on Quality of Life (QoL). Functional endoscopic sinus surgery (FESS) has proven to be an effective treatment, but it is still unclear what long-term outcomes are in children with CRSwNP. The objective of this study was to assess long-term results of FESS in children with CRSwNP. METHODOLOGY: We performed a combined prospective and retrospective study. A QoL questionnaire was send to all children with CRSwNP who received FESS between the year 2000-2010. Almost half of these children also filled in this questionnaire preoperatively. RESULTS: Forty-four Children underwent FESS. From 18 patients, we also prospectively collected preoperative QoL questionnaires. The mean follow-up period was 4.0 years (+- 2.9). The mean age at surgery was 13 years (+-2.9). Of these children, 9 had CF and 10 children asthma. R-SOM scores showed a significant improvement both in general symptoms as well as several different domains when comparing pre- and postoperative questionnaires. Only 5 of 44 patients needed a subsequent intervention. In children with CF this was 3 of 9. CONCLUSION: This study demonstrates that long-term results of FESS in children with CRSwNP are good. QoL has improved significantly, especially in nasal symptoms, showing that FESS is a good treatment in children with CRSwNP. Furthermore, even children with CF show good results.

Effects of alvocidib and carboplatin on ovarian cancer cells in vitro.

AIM: Failure of platinum chemotherapy is an unresolved issue in ovarian cancer. Targeted therapy has been added to the treatment options in solid cancers. Alvocidib is a cyclin dependent kinase inhibitor. MATERIALS AND METHODS: This study evaluated the effects of alvocidib together with carboplatin on ovarian cancer cells (BG-1 and Skov-3) in vitro applying proliferation assays, cell cycle distribution analyses, apoptosis induction assays, and drug accumulation assay. RESULTS: Proliferation of both cell lines was inhibited by carboplatin and alvocidib. The interaction index revealed drug synergism at distinct drug concentrations. Cell cycle distribution was altered. Alvocidib induced apoptosis in Skov-3 cells, and necrosis in BG-1 cells. Rhodamine accumulation was increased by alvocidib or both compounds together. CONCLUSION: These data provide evidence for antiproliferative effects of alvocidib on human ovarian cancer cells in vitro associated with changes in cell cycle distribution, the induction of apoptosis, and modulation of intracellular drug accumulation. Alvocidib and carboplatin showed some cooperative activity.

Nasal hyper-reactivity is a common feature in both allergic and nonallergic rhinitis.

BACKGROUND: Nasal hyper-reactivity is an increased sensitivity of the nasal mucosa to various nonspecific stimuli. Both allergic rhinitis (AR) and nonallergic rhinitis (NAR) patients can elicit nasal hyper-reactivity symptoms. Differences in the prevalence or type of nasal hyper-reactivity in AR and NAR patients are largely unknown. In this study, we quantitatively and qualitatively assessed nasal hyper-reactivity in AR and NAR. METHODS: In the first part, an analysis of a prospectively collected database was performed to reveal patient-reported symptoms of hyper-reactivity. In the second part, cold dry air provocation (CDA) was performed as a hyper-reactivity measure in AR and NAR patients and healthy controls, and symptoms scores, nasal secretions and peak nasal inspiratory flow were measured. Comparisons were made between AR and NAR patients in both studies. RESULTS: The database analysis revealed high hyper-reactivity prevalence in AR (63.4%) and NAR (66.9%). There were no differences between AR and NAR in terms of the number or type of hyper-reactivity stimuli. Hyper-reactivity to physical stimuli did not exclude a response to chemical stimuli, or vice versa. CDA provocation resulted in a significant increase in rhinitis symptoms and the amount of nasal secretions in AR and NAR patients, but not in controls. CONCLUSIONS: We found no quantitative or qualitative differences in nasal hyper-reactivity between AR and NAR patients. It is not possible to differentiate NAR subpopulations based on physical or chemical stimuli.

Inverse PPARß/δ agonists suppress oncogenic signaling to the ANGPTL4 gene and inhibit cancer cell invasion.

Besides its established functions in intermediary metabolism and developmental processes, the nuclear receptor peroxisome proliferator-activated receptor ß/δ (PPARß/δ) has a less defined role in tumorigenesis. In the present study, we have identified a function for PPARß/δ in cancer cell invasion. We show that two structurally divergent inhibitory ligands for PPARß/δ, the inverse agonists ST247 and DG172, strongly inhibit the serum- and transforming growth factor ß (TGFß)-induced invasion of MDA-MB-231 human breast cancer cells into a three-dimensional matrigel matrix. To elucidate the molecular basis of this finding, we performed chromatin immunoprecipitation sequencing (ChIP-Seq) and microarray analyses, which identified the gene encoding angiopoietin-like 4 (ANGPTL4) as the major transcriptional PPARß/δ target in MDA-MB-231 cells, previously implicated in TGFß-mediated tumor progression and metastatic dissemination. We show that the induction of ANGPTL4 by TGFß and other oncogenic signals is strongly repressed by ST247 and DG172 in a PPARß/δ-dependent fashion, resulting in the inhibition of ANGPTL4 secretion. This effect is attributable to these ligands' ability to induce a dominant transcriptional repressor complex at the site of transcription initiation that blocks preinitiation complex formation through an histone deacetylase-independent, non-canonical mechanism. Repression of ANGPTL4 transcription by inverse PPARß/δ agonists is functionally linked to the inhibition of cancer cell invasion into a three-dimensional matrix, as (i) invasion of MDA-MB-231 cells is critically dependent on ANGPTL4 expression, (ii) recombinant ANGPTL4 stimulates invasion, and (iii) reverses the inhibitory effect of ST247 and DG172. These findings indicate that a PPARß/δ-ANGPTL4 pathway is involved in the regulation of tumor cell invasion and that its pharmacological manipulation by inverse PPARß/δ agonists is feasible.

Quality of life in extended endonasal approaches for skull base tumours.

OBJECTIVE: To assess the quality of life (QOL) impact of extended endonasal approaches and nasoseptal flap reconstruction for benign skull base tumours METHODS: A random sample of 110 patients undergoing either limited endonasal transphenoidal hypophysectomy or extended endonasal approaches (trans-cribriform, trans-sellar, trans-tuberculum, trans-pterygoid) for the removal of benign skull base tumours were asked to complete Rhinosinusitis Outcome Measure (RSOM-31) questionnaire. RESULTS: A total of 91 patients returned the completed questionnaire. All patients in the limited approach group had pituitary adenomas, while patients in the extended group had a variety of tumours including adenomas with suprasellar or cavernous extension, chordomas, meningiomas, craniopharyngiomas and dermoids. Median time to completion of questionnaire was 1104 days in the limited group and 142 days in the extended approaches group. Although smell and headache were significantly worse in the group undergoing reconstruction with Haddad flap, there was no significant difference in overall, nasal, general, emotional or sleep quality of life between the two groups. Both smell and headache showed significant improvement with time. In linear regression, the single most important factor independently associated with overall worse RSOM-31 total scores was the presence of secreting adenomas. CONCLUSION: The use of nasoseptal flap appears to have a limited negative impact in nasal quality of life, mainly related to heada- che and reduced smell, both of which tend to improve with time. Hormone-secreting tumours have the most important adverse effect in quality of life extending in general, emotional, sleep and overall wellbeing, as reflected in RSOM 31 subscales.

Reconstructions with identical filling (RIF) of the heart: a physiological approach to image reconstruction in coronary CT angiography.

OBJECTIVES: To compare image quality in coronary artery computed tomography angiography (cCTA) using reconstructions with automated phase detection and Reconstructions computed with Identical Filling of the heart (RIF). METHODS: Seventy-four patients underwent ECG-gated dual source CT (DSCT) between November 2009 and July 2010 for suspected coronary heart disease (n = 35), planning of transcatheter aortic valve replacement (n = 34) or evaluation of ventricular function (n = 5). Image data sets by the RIF formula and automated phase detection were computed and evaluated with the AHA 15-segment model and a 5-grade Likert scale (1: poor, 5: excellent quality). Subgroups regarding rhythm (sinus rhythm = SR; arrhythmia = ARR) and potential premedication were evaluated by a per-segment, per-vessel and per-patient analysis. RESULTS: RIF significantly improved image quality in 10 of 15 coronary segments (P < 0.05). More diagnostic segments were provided by RIF regarding the entire cohort (n = 693 vs. 590, P < 0.001) and all of the subgroups (e.g. ARR: n = 143 vs. 72, P < 0.001). In arrhythmic patients (n = 19), more diagnostic vessels (e.g. LAD: n = 10 vs. 3; P < 0.014) and complete data sets (n = 7 vs. 1; P < 0.001) were produced. CONCLUSIONS: RIF reconstruction is superior to automatic diastolic non-edited reconstructions, especially in arrhythmic patients. RIF theory provides a physiological approach for determining the optimal image reconstruction point in ECG-gated CT angiography. KEY POINTS: Conventional CT coronary angiography suffers from numerous artefacts in patients with irregular rhythms. Coronary computed tomography angiograms (cCTA) were reconstructed with identical cardiac filling (RIF). RIF reconstructions provide improved image quality compared to non-edited standard reconstructions. RIF theory links physiology with cardiac CT.

The microdebrider, a step forward or an expensive gadget?

BACKGROUND: Although the use of the microdebrider (shaver) is well known in endoscopic sinus surgery (FESS), there is lack of evidence from comparative studies focussing on the difference in operating time, intra-operative blood loss and user-friendliness between the microdebrider and traditional operating techniques. In this study we compared the use of the microdebrider to conventional instruments in FESS in these areas. METHODS: A prospective randomised double blind controlled trial in 60 patients with chronic rhinosinusitis with nasal polyposis (CRSwNP) undergoing bilateral FESS. Each subject received FESS using only traditional instruments (Blakseley forceps) on one side and the other side with the additional use of the microdebrider, this way serving as their own control. The primary outcome was operation time, intra-operative blood loss and user friendliness and secondly safety and postoperative healing with a follow-up period at different time points up to three months postoperative. RESULTS: We found a 37% longer operating time when operating without a microdebrider. This difference was highly significant. The microdebrider scored significantly higher on every different parameter of user friendliness, except on the preparation of the instrument needed before surgery. For estimated blood loss during surgery we found no differences. Also there was no significant difference in postoperative healing at any point of time. CONCLUSIONS: This study demonstrates that operating patient with CRSwNP with the microdebrider is efficient and that the microdebrider at the same time is safe and easy to use.

Long-term low-dose antibiotics in recalcitrant chronic rhinosinusitis: a retrospective analysis.

INTRODUCTION: In recalcitrant Chronic RhinoSinusitis (CRS) treatment with intranasal corticosteroids, short-term antibiotics and even sinus surgery is frequently insufficient. Long-term low-dose administration of antibiotics has been suggested as a treatment option in these patients. We analysed the outpatient clinic population treated with different long-term low-dose antibiotics at the AMC Amsterdam. PATIENTS AND METHODS: Eligible patients, who were treated with trimethoprim-sulfamethoxazole or macrolides, were retrospectively identified from our outpatient clinic in 2009. The two main outcome measures were sinonasal complaints and nasal endoscopic findings. A 5-point grading scale was used to score the results compared with the pre-treatment situation. This was measured at several time-points during, and after the antibiotic course, and at the end of the follow-up term. RESULTS: Seventy-six patients were included, 53 per cent had asthma and all of them had undergone sinus surgery. Seventy-eight per cent showed improvement of the symptoms, and 84 per cent demonstrated improvement of the sinonasal mucosa at the end of the course. No significant difference was found between the trimethoprim-sulfamethoxazole and macrolide group. DISCUSSION: Long-term low-dose treatment with antibiotics seems to improve CRS symptoms and the appearance of the sinonasal mucosa on nasal endoscopy. However, at this stage, strong conclusions are immature because no placebo-group has been included. Despite increasing use of long-term low-dose treatment of recalcitrant CRS in referral centres, hard clinical evidence is lacking. More research is urgently required.

Plasmacytoid dendritic cells in pulmonary lymphoid follicles of patients with COPD.

Plasmacytoid dendritic cells (pDCs) are professional antigen-presenting cells with antiviral and tolerogenic capabilities. Viral infections and autoimmunity are proposed to be important mechanisms in the pathogenesis of chronic obstructive pulmonary disease (COPD). The study aimed to quantify blood dendritic cell antigen 2-positive pDCs in lungs of subjects with or without COPD by immunohistochemistry and flow cytometry, combined with the investigation of the influence of cigarette smoke extract (CSE) on the function of pDCs in vitro. pDCs were mainly located in lymphoid follicles, a finding compatible with their expression of lymphoid homing chemokine receptors CXCR3 and CXCR4. pDC accumulated in the lymphoid follicles and in lung digests of patients with mild to moderate COPD, compared with smokers without airflow limitation and patients with COPD Global Initiative for Chronic Obstructive Lung disease (GOLD) stage III-IV. Exposing maturing pDC of healthy subjects to CSE in vitro revealed an attenuation of the expression of co-stimulatory molecules and impaired interferon-α production. Maturing pDC from patients with COPD produced higher levels of tumour necrosis factor (TNF)-α and interleukin (IL)-8 compared to pDC from healthy subjects. CSE significantly impairs the antiviral function of pDCs. In COPD, a GOLD stage dependent accumulation of pDC in lymphoid follicles is present, combined with an enhanced production of TNF-α and IL-8 by maturing pDCs.