Biomedical subjects

Mark Jorissen

Publications and source records attributed to Mark Jorissen.

15 recordsLinked to original sources

PubMed2006

IL-10- and IL-12-independent down-regulation of allergic sensitization by stimulation of CD40 signaling.

Interaction between CD154 (CD40 ligand) on activated T lymphocytes and its receptor CD40 has been shown to be critically involved in the generation of cell-mediated as well as humoral immunity. CD40 triggering activates dendritic cells (DC), enhances their cytokine production, up-regulates the expression of costimulatory molecules, and induces their maturation. It is unknown how stimulation of CD40 during sensitization to an airborne allergen may affect the outcome of allergic airway inflammation. We took advantage of a mouse model of allergic asthma and a stimulatory mAb to CD40 (FGK45) to study the effects of CD40-mediated DC activation on sensitization to OVA and subsequent development of OVA-induced airway inflammation. Agonistic anti-CD40 mAb (FGK45) injected during sensitization with OVA abrogated the development of allergic airway inflammation upon repeated airway challenges with OVA. Inhibition of bronchial eosinophilia corresponded with reduced Th2 cytokine production and was independent of IL-12, as evidenced by a similar down-regulatory effect of anti-CD40 mAb in IL-12 p40-deficient mice. In addition, FGK45 equally down-regulated allergic airway inflammation in IL-10-deficient mice, indicating an IL-10-independent mechanism of action of FGK45. In conclusion, our results show that CD40 signaling during sensitization shifts the immune response away from Th2 cytokine production and suppresses allergic airway inflammation in an IL-12- and IL-10-independent way, presumably resulting from enhanced DC activation during sensitization.

Animals↗

PubMed2006

Localization of candidate regions for a novel gene for Kartagener syndrome.

Asymmetric positioning of internal organs is a characteristics of vertebrates. The normal left-right anatomic positioning, situs solitus, sometimes does not occur normaly, leading to laterality defects. Studies in animal models have shown that laterality decisions are mediated by a cascade of genes that lead to the asymmetric expression of Nodal, LEFTA, LEFTB and PITX2 in the lateral plate mesoderm. A search for mutations in genes implicated in left-right patterning in animal models allowed genes associated with heterotaxia defects in humans to be identified. However, these genes explain only a small percentage of human situs defects, suggesting that other genes must play a role. In this study, we report a consanguineous family of Turkish origin, composed of two unaffected parents and three children, two of whom presented Kartagener syndrome. On the basis of their family history, we hypothesize autosomal recessive mode of inheritance. A genotype analysis with polymorphic markers did not show linkage with any known genes or loci causing laterality disorders. Array CGH did not detect a duplication or microdeletion greater than 1 Mb as a possible cause. Genome wide screening using 10 K Affymetrix SNP chips was performed, allowing the identification of two regions of autozygosity, one in chromosome 1 and the other on chromosome 7. In the chromosome 1 locus, a strong candidate gene, encoding the kinesin-associated protein 3 (KIF3AP) was not mutated, based on SSCP/heteroduplex analysis and direct sequencing. These data provide a basis for the identification of a novel gene implicated in Kartagener syndrome.

5' Untranslated Regions↗

PubMed2006

A randomized controlled trial of mometasone furoate nasal spray for the treatment of nasal polyposis.

OBJECTIVE: To evaluate the efficacy and safety of mometasone furoate nasal spray (NS) for the treatment of nasal polyposis. DESIGN: Randomized, double-blind, placebo-controlled, parallel-group, multicenter study. SETTING: A total of 24 centers in 17 countries. PATIENTS: A total of 310 subjects 18 years or older with bilateral nasal polyps. INTERVENTIONS: (1) A 200-microg dose of mometasone furoate NS in the morning and matching placebo in the evening; (2) 200-microg doses of mometasone furoate NS in the morning and evening; or (3) matching placebo in the morning and evening. All 3 regimens were administered as a nasal spray for 4 months. MAIN OUTCOME MEASURES: Primary end points were change from baseline to last assessment in physician-assessed bilateral polyp grade and change from baseline in subject-assessed congestion and/or obstruction score averaged over the first month of treatment. Analysis of variance was used for all efficacy end points except for change in bilateral polyp grade, for which baseline polyp grade was added as a covariate to the analysis of variance model to account for any between-group baseline differences in this variable. RESULTS: Mometasone furoate NS doses of 200 microg administered once or twice daily produced greater reductions in bilateral polyp grade at the end point than placebo, with differences reaching statistical significance with twice-daily dosing (P = .04). Over 1 month, both mometasone furoate NS regimens produced statistically superior improvements from baseline in congestion and/or obstruction score vs placebo (P = .01 for once-daily dosing; P<.001 for twice-daily dosing). The drug was well tolerated. CONCLUSION: Mometasone furoate NS is an effective and well-tolerated treatment for bilateral nasal polyposis in adults, reducing nasal polyp size and symptoms of nasal congestion and/or obstruction.

Administration, Intranasal↗

PubMed2006

Amphotericin B nasal lavages: not a solution for patients with chronic rhinosinusitis.

BACKGROUND: Chronic rhinosinusitis (CRS) is one of the most common chronic diseases. Recently, it has been suggested that an exaggerated immune response to fungi is crucial in the pathogenesis of the disease. On the basis of this hypothesis, intranasal treatment with amphotericin B should benefit patients with CRS. Data from 2 uncontrolled and 2 controlled trials are conflicting, however. OBJECTIVE: To clarify the role of intranasal antifungal drugs in the treatment of CRS, we conducted a large, double-blind, placebo-controlled, multicenter study comparing the effectiveness of amphotericin B nasal lavages with placebo. METHODS: A total of 116 randomly selected patients with CRS were instructed to instill 25 mL amphotericin B (100 microg/mL) or placebo to each nostril twice daily for 3 months. Primary outcomes included a reduction in total visual analog scale (VAS) score and nasal endoscopy score. Secondary outcome measures included peak nasal inspiratory flow, polyp score, quality of life (Short Form-36, Rhinosinusitis Outcome Measure-31), and individual VAS scores. RESULTS: Analysis was based on intention to treat and involved all patients randomly assigned. Mean VAS scores, Short Form-36 and Rhinosinusitis Outcome Measure-31 data, peak nasal inspiratory flow values, nasal endoscopy scores, and polyp scores were similar in both treatment groups at the time of randomization, and no significant differences were observed after 13 weeks of treatment. CONCLUSION: Amphotericin B nasal lavages in the described dosing and time schedule do not reduce clinical signs and symptoms in patients with CRS. CLINICAL IMPLICATIONS: Amphotericin B nasal lavages in the described dosing and time schedule are ineffective and therefore not advised in the treatment of patients with CRS.

Administration, Intranasal↗

PubMed2006

Long term effects of cutting forceps in endoscopic sinus surgery.

BACKGROUND: At present, some authors prefer cutting forceps to conventional non-cutting forceps in Endoscopic Sinus Surgery, based on the assumption of superior wound healing due to mucosal preservation, without any proof of better clinical outcome. The purpose of this study was to elaborate our previously reported short-term results, by evaluating the long-term outcome. METHODS: One hundred consecutive patients, who underwent a bilateral Endoscopic Sinus Surgery procedure, received follow-up in a prospective, double-blinded way. Cutting forceps had been randomly used on one side and non-cutting forceps on the other side. Lateralised symptoms (headache, maxillary pressure, nasal obstruction and secretions) and endoscopic findings (secretion, pus, blood, crusts, oedema, polyps and adhesions) were evaluated on both sides 1 year postoperatively. RESULTS: Both types of instruments gave satisfactory healing situations. Similar to the short-term follow-up results, no significant difference in the global symptom and endoscopic score between the 2 types of instruments was found. The analysis of individual symptoms and endoscopic parameters also showed no difference. CONCLUSION: Cutting forceps do not result in a better subjective or endoscopic healing evaluation after one year, compared to non-cutting forceps.

Double-Blind Method↗

PubMed2005

High-speed digital imaging method for ciliary beat frequency measurement.

The aim of this study was to develop a high-speed digital imaging system and related software for ciliary beat frequency (CFB) analysis in order to establish an automated and reliable method that is observer independent and faster compared to the conventional computerized microscope photometry method. Using primary human nasal epithelial cell cultures, the CBF was recorded with a computerized microscope photometry system and a high-speed digital imaging system. To obtain a wide range of frequencies, glycocholate (0.5%) and chlorocresol (0.005%) were used as ciliostimulatory and cilio-inhibitory reference compounds, respectively. The mean values in hertz (+/- s.d.) obtained with the photometry and high-speed digital imaging systems were: controls 8.2 +/- 0.9 and 7.9 +/- 1.1; chlorocresol 5.0 +/- 0.9 and 5.1 +/- 1.1; glycocholate 9.8 +/- 1.0 and 9.7 +/- 0.8. A similar increase (by 20 and 24%) and decrease (by 38 and 35%) in CBF was determined by the two methods after glycocholate and chlorocresol treatment, respectively. The mean difference between the photometry and high-speed digital imaging methods was 0.2 +/- 0.6 Hz, and the Bland-Altman limits of agreement were from -1.0 to +1.4 Hz, suggesting that the results obtained by these two methods could be used interchangeably. These results show the reliability of the high-speed digital imaging system and the software developed for in-vitro CBF measurements. The advantages of the system include: (i) fast data acquisition and calculation, (ii) whole field automated CBF analysis and (iii) reduction in selection bias.

Cells, Cultured↗

PubMed2004

Sequential monolayer-suspension culture of human airway epithelial cells.

In this article, we describe a technique for culturing human airway epithelial cells, developed in Leuven, as a new tool for a most reliable diagnosis for ciliary disorders. This technique that allows to keep both structural and functional primary abnormalities of inherited ciliary abnormalities, while avoiding the secondary ones, can also be useful to a number of other studies, namely in cystic fibrosis.

Cell Culture Techniques↗

PubMed2004

Metabolism and absorption enhancement of methionine enkephalin in human nasal epithelium.

The objective of this study was to investigate absorption enhancing approaches for systemic delivery of methionine enkephalin via the nose. Absorption promotion of methionine enkephalin in the presence of protease inhibitors (bestatin, puromycin) and absorption enhancers (glycocholate, dimethyl-beta-cyclodextrin) were investigated in human nasal epithelium. Co-administration of the peptide with protease inhibitors and absorption enhancers resulted in a remarkable increase in Met-Enk permeation (4- to 94-fold). The increase was proportional to transepithelial resistance reduction and permeation of paracellular marker dye. Perturbation of the epithelial tight junctions seen in vitro may not occur in vivo due to mucus protection and mucociliary clearance.

Biological Transport↗

PubMed2004

The secondary nature of ciliary (dis)orientation in secondary and primary ciliary dyskinesia.

OBJECTIVE: Ciliary orientation (COR) is an important parameter of mucociliary clearance and ciliary disorientation has been reported in cases of acquired abnormalities [secondary ciliary dyskinesia (SCD)] and in a very few cases as the single abnormality in primary ciliary dyskinesia (PCD). The etiology, pathogenesis, consequences and relevance of ciliary (dis)orientation are still unclear. MATERIAL AND METHODS: To elucidate the primary or secondary nature of ciliary (dis)orientation, COR was measured in 179 non-PCD and 59 PCD patients. COR was measured in biopsies and after ciliogenesis in culture and was correlated with a number of functional and ultrastructural parameters. COR was defined as the SD of the angles of lines through the central pair of microtubules using transmission electron microscopy. Internationally accepted normal values for COR are < or = 20 degrees; COR values of 20-35 degrees indicate increased disorientation; and COR values > 35 degrees represent a random orientation. RESULTS: For non-PCD biopsies, COR increased with increasing SCD, from 15 +/- 7 degrees (n = 54) for normal (< 5%) SCD to 28 +/- 8 degrees (n = 16) for severe (> 25%) SCD. No correlation was found between COR and ciliary beat frequency. However, increased COR values (28 +/- 8 degrees) were found for immotility (n = 8), compared to (coordinated) ciliary activity (19 +/- 9 degrees) (n = 121). After ciliogenesis no ultrastructural abnormalities were found and COR was normal (13 +/- 5 degrees; n = 308). COR can therefore be considered to be secondary in non-PCD and correlates with SCD percentage and ciliary motility. In biopsies from PCD patients with dynein deficiency and with normal ultrastructure, COR was increased, to 28 +/- 11 degrees (n = 32) and 21 +/- 7 degrees (n = 15), respectively, and in cases with central pair abnormalities COR was random (38 +/- 11 degrees; n = 12). After ciliogenesis COR remained random in the PCD group with central pair abnormalities (38 +/- 9 degrees; n = 15), and was increased in the PCD groups with dynein deficiency (24 +/- 10 degrees; n = 35) and normal ultrastructure (25 +/- 8 degrees; n = 17). Ciliary disorientation was never found as the single abnormality. CONCLUSION: COR can be considered to be secondary in PCD. Both ciliary (im)motility and SCD percentage contribute to COR.

Cilia↗

PubMed2004

Postoperative care following endoscopic sinus surgery.

Postoperative care is very important in the global management of the patient undergoing ESS. Postoperative tamponnade, packing, splinting or stenting is advocated by many surgeons, but its clinical beneficial effects have not clearly been demonstrated. Postoperative rinsing/washing of the surgical cavity offers advantages in healing: high volume, low pressure is to be preferred. Suction cleaning is advocated on a weekly basis starting one week after ESS and continues until secretions, blood, crusts have disappeared. Topical medications have not been the subject of randomized clinical trials. Of the various classes of systemic (oral) medications, only steroids resulted in better short term outcome when using higher doses compared to lower doses. Antibiotics have not shown clinical effects and should not routinely be given.

Anti-Bacterial Agents↗

PubMed2003

Mechanistic appraisal of the effects of some protease inhibitors on ciliary beat frequency in a sequential cell culture system of human nasal epithelium.

The aim of this study was to investigate the suitability of a sequential monolayer-suspension culture system as a model to screen subacute effects of drug excipients on ciliary beat frequency (CBF). The CBF of the cultured cells was measured by computerized microscope photometry. Protease inhibitors (puromycin, bestatin, bacitracin, actinonin and thiomersal) were used as model compounds and the mechanisms of ciliary inhibition were investigated by probing the involvement of arachidonic acid metabolism, guanylate cyclase (cGMP), protein kinase C (PKC) and adenosinetriphosphate (ATP) inhibition. Bestatin concentration-dependently reduced CBF by inhibiting arachidonic acid metabolism, cGMP, PKC and endogenous ATP consumption. Thiomersal and DMSO used for dissolving actinonin reduced CBF (P<0.05) via a non-specific mechanism. Bacitracin (8 mM) and puromycin (135 mM) had no effect on CBF after acute exposure (15-30 min) (P>0.05), but significantly reduced the CBF by approximately 15.0% following daily 15-min exposure for 1 week. This study shows that (i) sequential monolayer-suspension culture system is a valid model to screen both acute and subacute effects of drug excipients on CBF; and (ii) bacitracin, puromycin and actinonin are more cilio-compatible than bestatin and thiomersal and as such are more potentially useful nasal absorption enhancer from ciliotoxicity perspective.

Cell Culture Techniques↗

PubMed2003

In vitro polarized transport of L-phenylalanine in human nasal epithelium and partial characterization of the amino acid transporters involved.

PURPOSE: The purpose of this study was to provide functional and molecular evidence to support the existence of large neutral amino acid transporters in human nasal epithelium using nasal primary cell culture model. METHODS: L-Phenylalanine was used as a model substrate to characterize carrier-mediated permeation of amino acids across human nasal epithelium. The influence of temperature, concentration, other amino acids, metabolic/transport inhibitors, and polarity/stereo-selectivity on transport of the model compound was investigated. Reverse transcriptase polymerase chain reaction was used for molecular characterization of the existence of the transporters. RESULTS: The transport of L-phenylalanine across the human nasal epithelium was polarized (apical --> basolateral >> basolateral --> apical), saturable (Km = 1.23 mM; Vmax = 805.1 nmol/mg protein/min) and stereo-selective (permeation of L-phenylalanine >> D-Phenylalanine). Its permeation was significantly (< 0.05) reduced by cationic, small and large neutral amino acids, oubain, amiloride, sodium-free medium, and temperature lowering. Reverse transcriptase polymerase chain reaction revealed the presence of the broad-scope cationic-dependent amino acid transporter gene (y+LAT-2) in the human nasal epithelium. CONCLUSIONS: Based on the results of this study, one may postulate that the human nasal epithelium expresses L-amino acid transporters. More studies are necessary for detailed characterization of the transporters.

Amino Acid Transport Systems↗

PubMed2002

Mutations in the DNAH11 (axonemal heavy chain dynein type 11) gene cause one form of situs inversus totalis and most likely primary ciliary dyskinesia.

Primary ciliary dyskinesia (PCD; MIM 242650) is an autosomal recessive disorder of ciliary dysfunction with extensive genetic heterogeneity. PCD is characterized by bronchiectasis and upper respiratory tract infections, and half of the patients with PCD have situs inversus (Kartagener syndrome). We characterized the transcript and the genomic organization of the axonemal heavy chain dynein type 11 (DNAH11) gene, the human homologue of murine Dnah11 or lrd, which is mutated in the iv/iv mouse model with situs inversus. To assess the role of DNAH11, which maps on chromosome 7p21, we searched for mutations in the 82 exons of this gene in a patient with situs inversus totalis, and probable Kartagener syndrome associated with paternal uniparental disomy of chromosome 7 (patUPD7). We identified a homozygous nonsense mutation (R2852X) in the DNAH11 gene. This patient is remarkable because he is also homozygous for the F508del allele of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Sequence analysis of the DNAH11 gene in an additional 6 selected PCD sibships that shared DNAH11 alleles revealed polymorphic variants and an R3004Q substitution in a conserved position that might be pathogenic. We conclude that mutations in the coding region of DNAH11 account for situs inversus totalis and probably a minority of cases of PCD.

Axonemal Dyneins↗

PubMed2002

Nasal absorption enhancement strategies for therapeutic peptides: an in vitro study using cultured human nasal epithelium.

This study examined the potential usefulness of cultured human nasal epithelium as a model to investigate nasal absorption enhancement strategies for therapeutic peptides. The transport of leucine enkephalin (Leu-Enk) in the presence of bestatin and puromycin, respectively and various combinations of these protease inhibitors with absorption enhancers capable of inhibiting proteases or protecting peptides against protease degradation (glycocholate, dimethyl-beta-cyclodextrin (DM beta CD)) was studied. Epithelial membrane perturbation, protein leakage, bestatin/puromycin absorption and rebound aminopeptidase activity were used as toxicological end-points. The combination of puromycin with glycocholate or DM beta CD resulted in a higher absorption enhancement of Leu-Enk (9-14%) than when the absorption enhancers were combined with bestatin (1-3%) or when the inhibitors were used alone (2-4%). The higher absorption enhancement resulting from the combination of protease inhibitors with absorption enhancers caused a significant reduction of epithelial resistance and increased sodium fluorescein transport. Although only puromycin permeated the human nasal epithelium, both protease inhibitors induced a significant rebound aminopeptidase activity (25-61%), which can be associated with protein leakage (21-46%). This study highlighted (i) the potential usefulness of cultured human nasal epithelium as a model to study nasal absorption enhancement of therapeutic peptides; (ii) further studies using in vivo nasal models are required to ascertain whether the membrane perturbation and cytotoxicity observed with various combinations of the protease inhibitors and absorption enhancers really raise safety concerns.

Absorption↗

PubMedDate not supplied

Congenital nasal piriform aperture stenosis or bony inlet stenosis: a report of three cases.

BACKGROUND: Congenital nasal piriform aperture stenosis is an uncommon disorder causing nasal obstruction in neonates. Findings on computed tomography (CT) greatly facilitate the diagnosis. METHODS: Three cases of congenital nasal piriform aperture stenosis are reported, with an emphasis on CT findings. CONCLUSIONS: At birth, a diameter of the piriform aperture at the level of the inferior nasal meatus of > or =5 mm on CT may indicate a good chance of success using conservative treatment.

Constriction, Pathologic↗