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M Jorissen

Publications and source records attributed to M Jorissen.

At least 19 recordsLinked to original sources
PubMed2006

Aggravation of bronchial eosinophilia in mice by nasal and bronchial exposure to Staphylococcus aureus enterotoxin B.

BACKGROUND: The role of bacterial enterotoxins like Staphylococcus aureus enterotoxin B (SEB) in allergic asthma remains unknown. We used a mouse model of airway allergy to study the effects of nasal or bronchial contact with SEB on bronchial allergic inflammation. METHODS: The features of allergic asthma were induced in ovalbumin (OVA)-sensitized mice (days 1-13) by repeated exposures to nebulized OVA (days 33-37). Nasal or bronchial application of SEB was performed on three occasions (days 33-35-37), and the effects on bronchial inflammation, IgE titres and expression levels of mRNA for T helper type 2 cytokines and other inflammatory mediators were evaluated. RESULTS: Both nasal and bronchial SEB enhanced the allergen-induced bronchial inflammation, as reflected by more eosinophilic inflammation in the airway lumen and in bronchial tissue. Aggravation of experimental asthma correlated with higher expression of mRNA for IL-5, IL-4, IFN-gamma, IL-12 p40, eotaxin-1 and TGF-beta in bronchi. In addition, nasal SEB elevated concentrations of IL-4, IL-5 and IFN-gamma in serum and bronchial SEB increased titres of OVA-specific and total IgE in serum. CONCLUSION: Our data illustrate the potential of both nasal as well as bronchial SEB to aggravate several features of allergic asthma in a mouse model.

Acute Disease↗
PubMed2006

Levocetirizine as treatment for symptoms of seasonal allergic rhinitis.

OBJECTIVES: The aim of this study was to assess the effectiveness and safety of levocetirizine in the treatment of the symptoms of seasonal allergic rhinitis (SAR) in patients consulting their primary care doctor. METHODS: Open-label uncontrolled and non-randomised multi-centre study including patients presenting symptoms of SAR and treated with levocetirizine tablets, 5 mg OD, for 4 weeks. INCLUSION CRITERIA: patients with nasal symptoms who were not on treatment or not responsive to treatment, or affected by excessive adverse events due to the antihistamines used previously. There were two visits (initial and after four weeks). Primary end point: efficacy as measured by T4SS (combined score of sneezing, rhinorrhoea, nasal and ocular pruritus, ranging from 0 to 12 recorded by the patient); change in Clinical Global Impression (CGI-c) as rated by the general practitioner, subjective satisfaction with and preference for levocetirizine. Secondary end points: treatment-related adverse events. RESULTS: 1290 patients were evaluated. Before the start of the study, 61.2% did not use any medication, 36.4% took anti-histamines which were not effective, and 27.0% of those previously treated patients experienced excessive adverse events. Statistically significant decreases (p < 0.01) compared to baseline were observed for each individual symptom of the itemised T4SS as well as for the global T4SS. The CGI-c improved in 91.1% of the patients who had received treatment previously and 96.8% of those who had not. Of the patients who had received treatment previously, 91.7% (p < 0.01) were satisfied with the study treatment and 84.5% of these patients reported they would prefer levocetirizine in future. All adverse events (somnolence, fatigue, headache, dry mouth) decreased by comparison with previous treatments after levocetirizine was used. CONCLUSION: Levocetirizine showed an improvement in symptom control for SAR and was preferred by patients compared to the antihistamines they had taken previously. Levocetirizine was well tolerated.

Adolescent↗
PubMed2006

Routine pathological evaluation after tonsillectomy: is it necessary?

OBJECTIVES: There is still no consensus regarding the necessity of sending every tonsil specimen for histological examination following tonsillectomy. To add to this discussion, we assessed the incidence of preoperatively unexpected malignancy in the postoperative tonsil specimens of adults and children in our ENT department. METHODS: We conducted a retrospective study of the histopathology results of all patients who underwent tonsillectomy between January 1999 and February 2006 in the ENT department of East Limburg Hospital in Genk. The charts of patients with postoperative histopathological malignancy were further analysed and reviewed for preoperative indications of the tonsillectomy and for preoperative suspicion of malignancy. RESULTS: A total of 2989 patients were included in the study: 2058 children (defined as 16 years or younger) and 931 adults. No malignancy was found among the children. In 20 adults, malignancy was diagnosed, but in all cases there was a preoperative suspicion of malignancy. No patient without preoperative risk factors was found to have malignancy on pathological evaluation of the tonsils. CONCLUSION: Our results indicate that routine histopathological examination of tonsils removed for benign disease in adults and children is clinically unnecessary. We propose that on an individual basis, the surgeon should decide the need for histological examination depending on preoperative risk factors and peroperative gross examination. Such a strategy will only be medicolegally possible where there are national and scientifically (evidence)based ENT consensus reports or guidelines on this issue.

Adolescent↗
PubMed2006

Tonsillectomy as a day-case surgery: a safe procedure?

UNLABELLED: PROBLEM/OBJECTIVES: To assess the safety of tonsillectomy as a one-day procedure, we retrospectively evaluated complications of tonsillectomy within two weeks after surgery. METHODOLOGY: The study included 1977 patients; 85% of the tonsillectomies were performed as a one-day procedure. Tonsillectomies were performed in Ziekenhuis Oost Limburg by one staff ENT and seven ENT residents between January 1, 1996 and January 1, 2005. We also reviewed the number of tonsillectomies performed as day surgery and their complication rate for Belgium, based on the National Office for Health and Disability Insurance billing, comparing our series with the number of tonsillectomies as day-case surgeries and their complication rate for Belgium. RESULTS: In our study, 26 patients (1.3%) consulted within two weeks of surgery for major or minor complications secondary to tonsillectomy. The only major complication was primary bleeding (bleeding within 24 hours after tonsillectomy), which occurred in five patients, all of whom received a revision for haemostasis. No patient required transfusion. Minor complications (21 patients) were secondary bleeding, fever, and anorexia. During the study period, there were 214,524 tonsillectomies performed in Belgium. Based on invoice information, 4676 cases of postoperative bleeding occurred, requiring a revision for haemostasis. In our centre and generally for Belgium, there was an increase in tonsillectomies as an outpatient procedure without an increase in incidence of subsequent bleeding. Day-case surgery tonsillectomy incidence had risen from 36% in 1996 to 64% in 2004 in Belgium. CONCLUSION: Considering the low bleeding and complication rates, tonsillectomy can safely be performed as a day-case surgery.

Adolescent↗
PubMed2005

Stable ciliary activity in human nasal epithelial cells grown in a perfusion system.

PURPOSE: Explore the usefulness of a perfusion system in order to establish human nasal epithelial cell cultures suitable for long-term in vitro ciliary beat frequency (CBF) and cilio-toxicity studies. METHODS: The cells were obtained by protease digestion of nasal biopsy material. The cells were plated at a density of 0.8-1 x 10(6)/cm2 on Vitrogen-coated polyethylene terephthalate membranes, and cultured under submerged conditions in a CO2 incubator or in a perfusion system (initiated on days 8-9 after plating). The CBF was determined at 24.1 +/- 0.8 degrees C by a computerized microscope photometry system. The morphology of the cultured cells was characterized by transmission electron microscopy (TEM). RESULTS: Under CO2 incubator culture conditions, stable ciliary activity was expressed and maintained from day 2 to day 24. Under perfusion system culture conditions, the CBF (mean+/-S.D., n = 4) amounted to 8.4 +/- 0.9 and 8.8 +/- 0.4 Hz on days 7 and 14, respectively. These values were lower as compared to the corresponding CBF obtained in the CO2 incubator cultures (9.5 +/- 0.6 and 9.9 +/- 1.0 Hz, respectively). Reference cilio-stimulatory (glycocholate) and cilio-inhibitory (chlorocresol) compounds were used to assess CBF reactivity. In the CO2 incubator and 7- and 14-days perfusion system cultures, glycocholate (0.5%) showed a reversible cilio-stimulatory effect of 23, 26 and 21%, respectively, while chlorocresol (0.005%) exerted a reversible cilio-inhibitory effect of 36, 40 and 36%, respectively. TEM revealed polarized cuboidal to columnar epithelial morphology, with well-differentiated ciliated cells under CO2 and perfusion system conditions (up to day 23). CONCLUSION: Culturing human nasal epithelial cells on Vitrogen-coated polyethylene terephthalate membranes in submerged conditions in a CO2 incubator and in a perfusion system offers the possibility for long-term preservation (up to 22-24 days) of stable and reactive CBF in vitro.

Animals↗
PubMed2005

The use of human nasal in vitro cell systems during drug discovery and development.

The nasal route is widely used for the administration of drugs for both topical and systemic action. At an early stage in drug discovery and during the development process, it is essential to gain a thorough insight of the nasal absorption potential, metabolism and toxicity of the active compound and the components of the drug formulation. Human nasal epithelial cell cultures may provide a reliable screening tool for pharmaco-toxicological assessment of potential nasal drug formulations. The aim of this review is to give an overview of the information relevant for the development of a human nasal epithelial cell culture model useful during drug discovery and development. A primary goal in the development of in vitro cell culture systems is to maintain differentiated morphology and biochemical features, resembling the original tissue as closely as possible. The potential and limitations of the existing in vitro human nasal models are summarized. The following topics related to cell culture methodology are discussed: (i) primary cultures versus cell lines; (ii) cell-support substrate; (iii) medium and medium supplements; and (iv) the air-liquid interface model versus liquid-liquid. Several considerations with respect to the use of in vitro systems for pharmaceutical applications (transport, metabolism, assessment of ciliary toxicity) are also discussed.

Administration, Intranasal↗
PubMed2005

Mucociliary transport using 99mTc-albumin colloid: a reliable screening test for primary ciliary dyskinesia.

BACKGROUND: A study was undertaken to assess the reliability of the nasal mucociliary transport test using 99mTc-albumin colloid as a screening test for primary ciliary dyskinesia (PCD) and to compare it with the gold standard nasal biopsy for study of ciliary motility and ultrastructure. METHODS: During a 4 year period both tests were performed in 55 children referred with persistent or recurrent respiratory tract infections. Their median age was 4 years (range 1 month to 15 years). RESULTS: The nasal biopsy results were as follows: PCD, n = 8; secondary ciliary dyskinesia (SCD), n = 19; normal, n = 28. The mucociliary transport test was abnormal in 29 patients (all 8 with PCD, 7/19 with SCD, and 14/28 with a normal biopsy). The sensitivity of the mucociliary transport test to diagnose PCD was therefore 100% (8/8) (95% exact confidence limits 63.06 to 100.00); the specificity was only 55% (26/47) (40.95 to 69.89). The negative predictive value was 100% (26/26) (86.77 to 100.00) and the positive predictive value was 28% (8/29) (12.37 to 47.24). CONCLUSION: Mucociliary transport is a non-invasive screening test that can be performed even in infants. The sensitivity of the test is high but its specificity is low. A normal test result excludes PCD.

Adolescent↗
PubMed2005

Chronic maxillary atelectasis.

Chronic maxillary atelectasis (CMA) is characterized by a reduced maxillary sinus volume due to an inward bowing of one or more of the sinus walls. The disorder is probably caused by an obstruction of the maxillary ostium, leading to a persistent negative pressure within the sinus lumen. To provide insight into the epidemiology, pathogenesis and treatment of this disorder, a retrospective study of twelve cases that met radiographic criteria of CMA was carried out. The patients were equally divided between both sexes and were on average 25 years old. Five of the twelve patients were under eighteen years of age. The patients had chronic sinonasal complaints except two, who had a "silent sinus syndrome", characterized by enophthalmos associated with a marked sinus deformation. This is the first report of CMA associated with a benign nasal tumour and also of CMA following cicatrisation due to nasal packing for bleeding after endoscopic sinus surgery. All patients were treated surgically by creating a middle meatal antrostomy, thus restoring sinus ventilation. To conclude, CMA is rare and probably underestimated, especially in the paediatric population. Different entities causing a complete ostial occlusion can lead to CMA. Endoscopically restoring maxillary sinus ventilation is the recommended treatment.

Adult↗
PubMed2005

Risk factors for recurrence of paranasal sinus mucoceles after ESS.

OBJECTIVE: Paranasal sinus mucoceles are benign, expansive processes filled with mucus and bordered by respiratory mucosa. The purpose of our study was to determine risk factors for recurrence of mucoceles after endoscopic sinus surgery (ESS) based on clinical and radiological characteristics. METHODS: We performed a retrospective review of 57 patients consecutively treated endoscopically for mucoceles between 1992 and 2002 at the UZ Leuven, a tertiary referral university hospital. RESULTS: Paranasal sinus mucoceles predominantly occurred in the maxillary sinus and the fronto-ethmoidal region (both 35%). In 69% of patients there was a history of sinus surgery (51%) or facial trauma (18%). Recurrence occurred in 5 of 49 patients who were treated by ESS in elective circumstances, while four of eight patients who underwent ESS at the moment of acute infection had recurrence (p = 0.004). Although all recurrences following elective ESS occurred in mucoceles related to previous facial trauma or sinus surgery, this relationship was not statistically significant (p = 0.2). In three patients, significant extension outside the sinus wall was present; three other patients had multiple mucoceles. Presence of multiple mucoceles and significant extension outside the sinus walls were also risk factors for recurrence (p = 0.002 and p = 0.001, respectively). In one patient with recurrence, the frontal recess was damaged during previous ESS. CONCLUSIONS: Three conditions can be considered risk factors for mucocele recurrence after ESS: surgery at a moment of acute infection, presence of multiple mucoceles, and significant extension outside the sinus wall.

Adult↗
PubMed2005

Pneumosinus dilatans and orbital meningioma in neurofibromatosis type 2.

We report on a 9-year-old boy with neurofibromatosis type 2 and a progressive proptosis of the left eye. Imaging studies revealed a pneumosinus dilatans of the left ethmoidal and frontal sinuses and an adjacent left orbital mass. Incision biopsy of the orbital mass showed a meningiothelial meningioma. Orbital and intracranial meningiomas are frequently associated with pneumosinus dilatans. This report illustrates the relationship of pneumosinus dilatans, intra-orbital meningioma and neurofibromatosis type 2.

Child↗
PubMed2004

Jugular foramen schwannoma: surgical experience in six cases.

PURPOSE: Schwannomas of the lower cranial nerves are rare tumours. We have surgical experience in six patients. MATERIAL AND METHODS: We have retrospectively reviewed the files of the six patients with jugular foramen schwannomas that were treated in multidisciplinary collaboration in the departments of neurosurgery and ENT. RESULTS: From a clinical point of view, the most important finding was that these tumours usually mimic a vestibular schwannoma. The imaging findings however always allowed the differentiation. The surgical technique included in all cases a suboccipital approach for the intracranial part. When large, the extracranial extension had to be removed through a lateral cervical or transfacial approach. There was no mortality and minor morbidity, with good functional outcome. In subtotally removed tumours, recurrence occurred. CONCLUSION: A combined neurosurgical and ENT approach allows for safe removal of these often large skull base tumours.

Adult↗
PubMed2003

Safety-assessment of 3-methoxyquercetin as an antirhinoviral compound for nasal application: effect on ciliary beat frequency.

It has been shown that 5,7,3',4'-tetrahydroxy-3-O-methylflavone (3-MQ) exhibits antipicornaviral activity. In order to explore the potential of 3-MQ as an antirhinoviral compound for nasal application, the effect of 3-MQ on the ciliary beat frequency (CBF) of human nasal epithelial cells was studied in vitro in the absence or presence of solubility/absorption enhancers (hydroxypropyl-beta-cyclodextrin (HP-beta-CD) or polysorbate 80). Nasal epithelial cells were obtained by protease digestion of surgical specimens of human nasal polyps, and used at confluency. The effect of 3-MQ (2, 10, and 20 microg/ml), HP-beta-CD (1, 3, and 10% (w/v)), polysorbate 80 (0.1, 0.3, and 1% (w/v)), and of the combination of 3-MQ with 3% HP-beta-CD or 1% polysorbate 80, on the CBF was determined by computerized microscope photometry 15 min after incubation with the test compounds; recovery was determined 35 min after rinsing. HP-beta-CD at 1 and 3% did not affect CBF; a reversible decrease (by 37%) was observed at 10%. Polysorbate 80 caused a reversible cilio-inhibitory effect of 40, 53, and 49% at 0.1, 0.3, and 1%, respectively. At 2 and 10 microg/ml, 3-MQ showed a reversible cilio-stimulatory effect of 18 and 14%, respectively. Combined with 3% HP-beta-CD, the reversible cilio-stimulatory effect of 2 microg/ml 3-MQ was preserved, while 10 and 20 microg/ml 3-MQ did not affect the CBF. The combination of polysorbate 80 (1%) and 3-MQ decreased the CBF, which could be attributed to the presence of polysorbate 80. In conclusion, no ciliotoxic effect could be observed for 3-MQ (up to 20 microg/ml) in the absence or presence of HP-beta-CD (3%). The potential of this combination as an antirhinoviral formulation for nasal application will be further explored.

Administration, Intranasal↗
PubMed2003

Disruption of nasopharyngeal epithelium by pneumococci is density-linked.

BACKGROUND: The aim of this project was to study the influence of pneumococci on nasopharyngeal epithelial integrity as a function of time and pneumococcal density. MATERIALS AND METHODS: Cell layers of an in vitro model of human nasopharyngeal epithelium were inoculated with different pneumococcal strains. The transepithelial electrical resistance (TEER), a measure of the integrity of the cell layers, and the pneumococcal concentration in the apical fluid on the epithelial cells were measured at different times after inoculation. RESULTS: Pneumococci caused a decrease in the TEER when a density of 1 x 107 CFU mL-1 was reached. The growth rate of pneumococci in our in vitro model differed between the strains tested and, for the same strain, between in vitro culture on the epithelial cells and broth culture. Differences in timing of the onset of decrease in the TEER between strains were the result of differences in growth rate on the epithelial cells. Antibiotic-induced lysis of pneumococci caused an immediate decrease in the TEER of the cell layers. CONCLUSION: Pneumococci cause a decrease in the TEER at a density of 1 x 107 CFU mL-1. Our hypothesis is that this decrease in the TEER is the result of quorum-induced lysis of the pneumococci.

Electric Impedance↗
PubMed2003

Macrolides: more than just antibiotics?!

Macrolides are used primarily as antibiotics, but they may have other effects. This was first suggested after clinical experience showed that macrolides have an important therapeutic role some inflammatory airway diseases in which infection is not considered as an important etiologic factor. In vitro, ex vivo and in vivo experiments revealed that macrolides reinforce local defense mechanisms in the upper respiratory tract such as mucociliary clearance and epithelial impermeability. In addition, macrolides influence acute inflammation, by altering concentrations of cytokines and changing leucocyte functions. This paper aims to review the current knowledge on the non-antibiotic effects of macrolides on local defense mechanisms and acute inflammation in the upper respiratory tract.

Cytokines↗
PubMed2001

Isolation, in silico characterization and chromosomal localization of a group of cDNAs from ciliated epithelial cells after in vitro ciliogenesis.

BACKGROUND: Immotile cilia syndrome (ICS) or primary ciliary dyskinesia (PCD) is an autosomal recessive disorder in humans in which the beating of cilia and sperm flagella is impaired. Ciliated epithelial cell linings are present in many tissues. To understand ciliary assembly and motility, it is important to isolate those genes involved in the process. RESULTS: Total RNA was isolated from cultured ciliated nasal epithelial cells after in vitro ciliogenesis and expressed sequenced tags (ESTs) were generated. The functions and locations of 63 of these ESTs were derived by BLAST from two public databases. These ESTs are grouped into various classes. One group has high homology not only with the mitochondrial genome but also with one or more chromosomal DNAs, suggesting that very similar genes, or genes with very similar domains, are expressed from both mitochondrial and nuclear DNA. A second class comprises genes with complete homology with part of a known gene, suggesting that they are the same genes. A third group has partial homology with domains of known genes. A fourth group, constituting 33% of the ESTs characterized, has no significant homology with any gene or EST in the database. CONCLUSIONS: We have shown that sufficient information about the location of ESTs could be derived electronically from the recently completed human genome sequences. This strategy of EST localization should be significantly useful for mapping and identification of new genes in the forthcoming human genome sequences with the vast number of ESTs in the dbEST database.

Cells, Cultured↗
PubMed2001

Axonemal beta heavy chain dynein DNAH9: cDNA sequence, genomic structure, and investigation of its role in primary ciliary dyskinesia.

Dyneins are multisubunit protein complexes that couple ATPase activity with conformational changes. They are involved in the cytoplasmatic movement of organelles (cytoplasmic dyneins) and the bending of cilia and flagella (axonemal dyneins). Here we present the first complete cDNA and genomic sequences of a human axonemal dynein beta heavy chain gene, DNAH9, which maps to 17p12. The 14-kb-long cDNA is divided into 69 exons spread over 390 kb. The cDNA sequence of DNAH9 was determined using a combination of methods including 5' rapid amplification of cDNA ends, RT-PCR, and cDNA library screening. RT-PCR using nasal epithelium and testis RNA revealed several alternatively spliced transcripts. The genomic structure was determined using three overlapping BACs sequenced by the Whitehead Institute/MIT Center for Genome Research. The predicted protein, of 4486 amino acids, is highly homologous to sea urchin axonemal beta heavy chain dyneins (67% identity). It consists of an N-terminal stem and a globular C-terminus containing the four P-loops that constitute the motor domain. Lack of proper ciliary and flagellar movement characterizes primary ciliary dyskinesia (PCD), a genetically heterogeneous autosomal recessive disorder with respiratory tract infections, bronchiectasis, male subfertility, and, in 50% of cases, situs inversus (Kartagener syndrome, KS). Dyneins are excellent candidate genes for PCD and KS because in over 50% of cases the ultrastructural defects of cilia are related to the dynein complex. Genotype analysis was performed in 31 PCD families with two or more affected siblings using a highly informative dinucleotide polymorphism located in intron 26 of DNAH9. Two families with concordant inheritance of DNAH9 alleles in affected individuals were observed. A mutation search was performed in these two "candidate families," but only polymorphic variants were found. In the absence of pathogenic mutations, the DNAH9 gene has been excluded as being responsible for autosomal recessive PCD in these families.

Adenosine Triphosphate↗
PubMed2001

Aneurysmal bone cyst of the nose with 17p13 involvement.

We report on a 6-year-old girl with a polypoid mass, filling up the entire right nasal cavity as shown on a magnetic resonance imaging scan. Histologically, the tumor had the characteristics of an aneurysmal bone cyst, which is extremely rare in this location. Cytogenetic analysis disclosed a single (6:17)(p21;p13) translocation, confirming a specific genetic involvement in the development of aneurysmal bone cysts. Fluorescent in situ hybridization analysis mapped the putative gene between the p53 (17p13.1) and the Mieller-Dieker gene (17p13.3) loci.

Bone Cysts, Aneurysmal↗