Replantation of a lip thrown in the bin

Management of soft tissue avulsion after facial bites could be challenging in some situation. We presented the case of a 32 years old men suffering from a full thickness avulsion of the left lower lip and cheek after a dog bite. Even if the lip fragment was initially put on the bin, a microvascular replantation was performed. The vascularization was based on the left inferior labial artery. No veins were found. We used post-operative leech therapy to avoid venous congestion during 10 days. A large antibiotherapy was conducted. Adaptation of antibiotics blood concentration was also necessary due to the permanent bleeding caused by leech therapy. At the 6 month consultation, the patient recovered an impressive labial function and sensibility. Replantation gives the best functional and esthetical outcomes in these rare and complex cases. Artificial blood drainage, large antibiotic therapy and close post-operative follow-up are significant parts of the replantation success.

Oxidative stress induces unfolding protein response and inflammation in nasal polyposis

BACKGROUND

Nasal polyposis, a chronic inflammatory disease affecting the upper airways, is a valuable and accessible model to investigate the mechanisms underlying chronic inflammation. The main objective of this study was to investigate a potential involvement of the unfolded protein response (UPR) in the context of oxidative stress and inflammation in nasal epithelial cells from nasal polyps (NP).

METHODS

Epithelial cells from NP (n = 20) and normal mucosa (Controls, n = 15) in primary culture were analyzed by global proteomic approach and cell biology techniques for the glucose-regulated protein 78 (GRP78), the spliced X-box-binding protein 1 (sXBP-1), the glucose-regulated protein 94 (GRP94), and the calreticulin (immunoblot, mass spectrometry, immunocytochemistry).

RESULTS

Proteomics analysis of human nasal epithelial cells in culture revealed the activation of the unfolded protein response in NP. Systematic cell biology and biochemical analysis of two markers (GRP78, sXBP-1) in the presence and absence of oxidative stress in NP showed a susceptibility of the unfolded protein response to oxidative stress compared to controls at least partially linked to an abnormal redox state of the protein disulfide-isomerase 4. This unfolded protein response was correlated with mitochondrial depolarization and secretion of interleukin 8 (IL-8) and leukotriene B4 (LTB4) and was prevented by mitochondrial antioxidant.

CONCLUSIONS

We show the existence of UPR in nasal epithelial cells that is linked to oxidative stress leading to IL-8 and LTB4 secretions. These mechanisms may participate in chronic inflammation in nasal polyposis.

Abnormal respiratory cilia in non-syndromic Leber congenital amaurosis with CEP290 mutations

BACKGROUND

Leber congenital amaurosis (LCA) is the earliest and most severe inherited retinal degeneration. Isolated forms of LCA frequently result from mutation of the CEP290 gene which is expressed in various ciliated tissues.

METHODS

Seven LCA patients with CEP290 mutations were investigated to study otorhinolaryngologic phenotype and respiratory cilia. Nasal biopsies and brushing were performed to study cilia ultrastructure using transmission electron microscopy and ciliary beating using high-speed videomicroscopy, respectively. CEP290 expression in normal nasal epithelium was studied using real-time RT-PCR.

RESULTS

When electron microscopy was feasible (5/7), high levels of respiratory cilia defects were detected. The main defects concerned dynein arms, central complex and/or peripheral microtubules. All patients had a rarefaction of ciliated cells and a variable proportion of short cilia. Frequent but moderate and heterogeneous clinical and ciliary beating abnormalities were found. CEP290 was highly expressed in the neural retina and nasal epithelial cells compared with other tissues.

DISCUSSION

These data provide the first clear demonstration of respiratory cilia ultrastructural defects in LCA patients with CEP290 mutations. The frequency of these findings in LCA patients along with the high expression of CEP290 in nasal epithelium suggest that CEP290 has an important role in the proper development of both the respiratory ciliary structures and the connecting cilia of photoreceptors. The presence of respiratory symptoms in patients could represent additional clinical criteria to direct CEP290 genotyping of patients affected with the genetically heterogeneous cone-rod dystrophy subtype of LCA.

A 20-year experience of electron microscopy in the diagnosis of primary ciliary dyskinesia

Transmission electron microscopy (TEM) analysis of ciliary ultrastructure is classically used for the diagnosis of primary ciliary dyskinesia (PCD). We report our extensive experience of TEM analysis in a large series of patients in order to evaluate its feasibility and results. TEM analysis performed in 1,149 patients with suspected PCD was retrospectively reviewed. Biopsies (1,450) were obtained from nasal (44%) or bronchial (56%) mucosa in children (66.5%) and adults (33.5%). TEM analysis was feasible in 71.4% of patients and showed a main defect suggestive of PCD in 29.9%. TEM was more feasible in adults than in children, regardless of the biopsy site. Main defects suggestive of PCD were found in 76.9% of patients with sinopulmonary symptoms and in only 0.4% of patients with isolated upper and 0.4% with isolated lower respiratory tract infections. The defect pattern was similar in children and adults, involving dynein arms (81.2%) or central complex (CC) (18.8%). Situs inversus was never observed in PCD patients with CC defect. Kartagener syndrome with normal ciliary ultrastructure was not an exceptional condition (10.2% of PCD). In conclusion, TEM analysis is feasible in most patients and is particularly useful for PCD diagnosis in cases of sinopulmonary syndrome of unknown origin.

Muco-ciliary differentiation of nasal epithelial cells is decreased after wound healing in vitro

BACKGROUND

Epithelial damage and modifications of cell differentiation are frequent in airway diseases with chronic inflammation, in which transforming growth factor-beta1 (TGF-beta1) plays an important role. The aim of this study was to evaluate the differentiation of human nasal epithelial cells (HNEC) after wound healing and the potential effects of TGF-beta1.

METHODS

Basal, mucus, and ciliated cells were characterized by cytokeratin-14, MUC5AC, and betaIV tubulin immunodetection, respectively. Their expression was evaluated in situ in nasal polyps and in an in vitro model of wound healing in primary cultures of HNEC after wound closure, under basal conditions and after TGF-beta1 supplementation. Using RT-PCR, the effects of TGF-beta1 on MUC5AC and DNAI1 genes, specifically transcribed in mucus and ciliated cells, were evaluated.

RESULTS

In situ, high TGF-beta1 expression was associated with low MUC5AC and betaIV tubulin expression. In vitro, under basal conditions, MUC5AC expression remained stable, cytokeratin-14 expression was strong and decreased with time, while betaIV tubulin expression increased. Transforming growth factor-beta1 supplementation downregulated MUC5AC and betaIV tubulin expression as well as MUC5AC and DNAI1 transcripts.

CONCLUSION

After a wound, differentiation into mucus and ciliated cells was possible and partially inhibited in vitro by TGF-beta1, a cytokine that may be involved in epithelial remodeling observed in chronic airway diseases.

Rhinitis and epistaxis in patients treated by anti-angiogenic therapy

Anti-angiogenic therapies have a particular drug-related toxicity profile including hypertension, thrombosis, haemorrhages, and proteinuria. Moreover, patients treated by angiogenesis inhibitors present nasal symptoms including symptomatic rhinitis and epistaxis. For the first time, a new entity of "atrophic rhinitis" induced by angiogenesis inhibitors is described and revealed that angiogenesis inhibitors alter the differentiation of nasal epithelium. VEGF may act on epithelial cell proliferation and differentiation in nasal epithelium.

Matrix metalloproteinase-2 and -9 expression in sinonasal inverted papilloma

STATEMENT OF PROBLEM

Inverted papilloma (IP) is a proliferative lesion of the epithelium lining the sinonasal tract, characterized by marked propensity for recurrence and association with carcinoma. To determine a putative role of matrix metalloproteinase-2 (MMP-2) and MMP-9 in the establishment of IP, their expression was studied in IP.

METHODS

Archived surgical specimens from 15 IPs were studied using immunohistochemistry and compared to 12 nasal polyps (NP), a model of chronic respiratory mucosal inflammation, and to 6 control nasal mucosa (CM) samples obtained from snorers during turbinectomy. Within IP, MMP-2 and -9 expression was compared between tumoral areas with hyperplastic epithelium and non tumoral areas with nonhyperplastic epithelium.

RESULTS

In IP, MMP-2 and MMP-9 epithelial expression was not different compared to CM and NP. MMP-9 expression in submucosal inflammatory cells was not different between IP and CM or NP. However, within IP, a significantly increased number of MMP-9 positive inflammatory cells in the lamina propria adjacent to the hyperplastic epithelium was observed compared to the lamina propria adjacent to nonhyperplastic epithelium.

CONCLUSION

Our findings suggest that MMP 9 expressing inflammatory cells may be involved in the pathophysiology of IP.

Transforming growth factor-beta1 increases airway wound repair via MMP-2 upregulation: a new pathway for epithelial wound repair?

In vivo, transforming growth factor (TGF)-beta1 and matrix metalloproteinases (MMPs) present at the site of airway injury are thought to contribute to epithelial wound repair. As TGF-beta1 can modulate MMP expression and MMPs play an important role in wound repair, we hypothesized that TGF-beta1 may enhance airway epithelial repair via MMPs secreted by epithelial cells. We evaluated the in vitro influence of TGF-beta1 on wound repair in human airway epithelial cells cultured under conditions allowing differentiation. The results showed that TGF-beta1 accelerated in vitro airway wound repair, whereas MMP inhibitors prevented this acceleration. In parallel, we examined the effect of TGF-beta1 on the expression of MMP-2 and MMP-9. TGF-beta1 induced a dramatic increase of MMP-2 expression with an increased steady-state level of MMP-2 mRNA, contrasting with a slight increase in MMP-9 expression. To confirm the role of MMP-2, we subsequently evaluated the effect of MMP-2 on in vitro airway wound repair and demonstrated that the addition of MMP-2 reproduced the acceleration of wound repair induced by TGF-beta1. These results strongly suggest that TGF-beta1 increases in vitro airway wound repair via MMP-2 upregulation. It also raises the issue of a different in vivo biological role of MMP-2 and MMP-9 depending on the cytokine microenvironment.

RPGR is mutated in patients with a complex X linked phenotype combining primary ciliary dyskinesia and retinitis pigmentosa

INTRODUCTION

Primary ciliary dyskinesia (PCD) is a rare disease classically transmitted as an autosomal recessive trait and characterised by recurrent airway infections due to abnormal ciliary structure and function. To date, only two autosomal genes, DNAI1 and DNAH5 encoding axonemal dynein chains, have been shown to cause PCD with defective outer dynein arms. Here, we investigated one non-consanguineous family in which a woman with retinitis pigmentosa (RP) gave birth to two boys with a complex phenotype combining PCD, discovered in early childhood and characterised by partial dynein arm defects, and RP that occurred secondarily. The family history prompted us to search for an X linked gene that could account for both conditions.

RESULTS

We found perfect segregation of the disease phenotype with RP3 associated markers (Xp21.1). Analysis of the retinitis pigmentosa GTPase regulator gene (RPGR) located at this locus revealed a mutation (631_IVS6+9del) in the two boys and their mother. As shown by study of RPGR transcripts expressed in nasal epithelial cells, this intragenic deletion, which leads to activation of a cryptic donor splice site, predicts a severely truncated protein.

CONCLUSION

These data provide the first clear demonstration of X linked transmission of PCD. This unusual mode of inheritance of PCD in patients with particular phenotypic features (that is, partial dynein arm defects and association with RP), which should modify the current management of families affected by PCD or RP, unveils the importance of RPGR in the proper development of both respiratory ciliary structures and connecting cilia of photoreceptors.

[Nasal ciliary investigations for the diagnosis of primary ciliary dyskinesia in children]

Primary ciliary dyskinesia (PCD) is an autosomal recessive disorder, characterized by chronic infections of the upper and lower airways, associated in 50% of cases with situs inversus, therefore, corresponding to Kartagener's syndrome. PCD is suspected on clinical features, including bronchitis, rhinosinusitis and chronic otitis media beginning in early childhood. The recurring infections eventually lead to bronchiectasis. The clinical features of PCD have been ascribed to primary defects in cilia, which lead to impairment of mucociliary clearance. Ciliary investigations looking for abnormalities in ciliary motion and ultrastructure can be easily performed at nasal level. Quantitative ultrastructural study of cilia is performed in cases of abnormal ciliary motion and/or clinical symptoms highly suggestive of PCD. In PCD, all or most of the cilia are abnormal, all bearing the same ultrastructural defects, mainly concerning dynein arms. In older children, the detection of a very low nasal NO output could also be useful for the diagnosis of PCD. As soon as the ciliary investigations are easy to perform at the nasal level, they could help for a better detection of PCD. This strategy could be especially useful in cases of atypical presentations, which are underestimated as a cause of recurrent airway infections. Diagnosis of PCD is important in order to prevent the development of bronchiectasis and to avoid any unnecessary procedure.

Bases moléculaires des dyskinésies ciliaires primitives

INTRODUCTION

The primary ciliary dyskinesias (PCD) are rare diseases characterised by infection of the airways due to impaired muco-ciliary clearance. Half the patients have situs inversus making up Kartagener's syndrome.

STATE OF THE ART

Primary cilia play a role in development. In the adult ciliated cells occur mainly in the airways and the genital tract. The axoneme, the internal structure of the cilia, is made up of a central pair of microtubules surrounded by peripheral doublets carrying the inner and outer dynein arms. These multiprotein complexes are composed of chains of dynein whose ATPase activity is the basis of ciliary movement. Structural and functional abnormalities of the respiratory ciliated cells are the cause of PCD, diseases that are heterogeneous at both the genetic and ultrastructural levels.

PERSPECTIVES

There are more than two hundred axonemal proteins. The synthesis and assembly of these proteins are controlled by transcription factors and intraflagellar transport molecules respectively. The genes that code for these proteins are as numerous as candidate genes for PCD.

CONCLUSIONS

To date only two dynein genes, DNA11 and DNAH5, have been implicated and only in individuals suffering from PCD with absence of outer dynein arms.

Atypical Sinusitis in Adults Must Lead to Looking for Cystic Fibrosis and Primary Ciliary Dyskinesia

HYPOTHESES/OBJECTIVES:: In adults, purulent pansinusitis or nasal polyposis starting early in life or that is permanently infected or associated either with chronic bronchial infection, infertility, or situs inversus are uncommon. In these atypical cases of chronic sinusitis (ACS), a primary dysfunction of the mucociliary clearance can be suspected. Adult patients with ACS were therefore investigated to detect primary ciliary dyskinesia (PCD) or cystic fibrosis (CF).

STUDY DESIGN

Open, prospective study.

PATIENTS AND METHODS

Forty-two patients with ACS were investigated with ciliary beat frequency and ultrastructure analysis in nasal cells and cystic fibrosis transmembrane conductance regulator (CFTR) gene mutation analysis in blood leukocytes.

RESULTS

The diagnosis of PCD was confirmed in seven (17%) patients. At least one CFTR gene mutation was detected in 16 (38%) patients. The diagnosis of CF was suggested in three (7%) compound heterozygous patients. Another 13 (31%) patients were heterozygous for a CFTR gene mutation or a complex allele. Comparison of clinical features of ACS showed that only a family history of chronic sinusitis (P <.01) or chronic bronchitis (P <.02) and the presence of diffuse bronchiectasis (P <.0001) or serous otitis media (P <.0001) were significantly more frequent in PCD patients than in patients carrying CFTR gene mutations or those without PCD or CFTR gene mutations.

CONCLUSIONS

ACS should be considered a remarkable entity in which congenital abnormalities of epithelial cells are frequently detected (55% of patients). The higher frequency of mutations in ACS patients compared with the general population suggests that heterozygoty for CFTR gene mutation could be a sinusitis-causing status.

Aspergillus fumigatus causes in vitro electrophysiological and morphological modifications in human nasal epithelial cells

The role of the airway epithelium in the development of invasive aspergillosis in immunocompromised hosts has rarely been studied although patients at risk for this infection frequently have epithelial damage. We developed an in vitro model of primary culture of human nasal epithelial cells (HNEC) in air-liquid interface, which allows epithelial cell differentiation and mimics in vivo airway epithelium. We subsequently tested 7-day and 24-hour Aspergillus fumigatus filtrates on the apical side of HNEC to know whether A. fumigatus, the main species responsible for invasive aspergillosis, produces specific damage to the epithelial cells. The results were compared with those obtained with non-pathogenic filamentous fungi. Seven-day culture filtrates of A. fumigatus and Penicillium chrysogenum induced electrophysiological modifications whatever the fungus tested. In contrast, only 24-hour A. fumigatus filtrates induced a specific decrease in transepithelial resistance, hyperpolarization of the epithelium, and cytoplasmic vacuolization of HNEC compared with both A. niger and Penicillium chrysogenum. The inhibition of the A. fumigatus effects with amiloride suggests that the 24-hour fungal filtrate acts through sodium channels of HNEC. These early modifications of the epithelial cells could facilitate colonization of the airways by A. fumigatus. To know whether the molecules involved are specific to A. fumigatus or simply produced more rapidly than by other filamentous fungi warrants further investigation. In this perspective, the primary culture of HNEC represents a suitable model to study the interactions between airway epithelial cells and A. fumigatus.

Abnormal central complex is a marker of severity in the presence of partial ciliary defect

BACKGROUND

Ciliary ultrastructural defects with total lack of dynein arms (DA) cause abnormal mucociliary function leading to the chronic infections observed in primary ciliary dyskinesia. The role of partial ciliary ultrastructural defects, especially those involving the central complex, and their relationship with respiratory symptoms have been less thoroughly investigated.

OBJECTIVE

In a pediatric population with partial ciliary defects, we determined the relationship(s) between ultrastructural findings, ciliary motility, and clinical and functional features, and evaluated the outcome of this population.

DESIGN

We analyzed the clinical presentation and pulmonary function of 43 children with chronic bronchitis and partial ultrastructural defects (from 15% to 90%) of their respiratory cilia demonstrated on bronchial biopsies. The study population was divided into 3 groups according to ciliary ultrastructure: the main ultrastructural defect concerned the central complex in 23 patients (CC group), peripheral microtubules in 8 patients (PMT group), and DA in 12 patients (DA group).

RESULTS

The percentage of ciliary defects was lower in the PMT group than in the CC and DA groups. Patients in the PMT group had less severe disease with frequent normal ciliary motility. Patients in the CC group had initially a higher incidence of respiratory tract infections, extensive bronchiectasis frequently requiring surgery, and arguments in favor of a congenital origin (high proportion of sibling form). Partial absence of DA, although of congenital origin, was associated with a good prognosis. In all groups, follow-up showed that the functional prognosis remained good with appropriate treatment.

CONCLUSIONS

In children with chronic respiratory infections, presence of situs inversus, sibling form, obstructive pulmonary syndrome, or bronchiectasis required ultrastructural analysis, regardless of ciliary motility. Detection of CC abnormalities is a marker of severity and required intensive therapy and close follow-up.

Efficacy and tolerance of intranasal insulin administered during 4 months in severely hyperglycaemic Type 2 diabetic patients with oral drug failure: a cross-over study

AIMS

We have evaluated the local tolerance and the metabolic efficacy of a lyophilized nasal insulin preparation in 10 severely hyperglycaemic Type 2 diabetic patients.

METHODS

The study included two 4-month randomized periods: (A) three preprandial doses of nasal insulin secondarily combined with one evening subcutaneous NPH if the desired glycaemic control was not achieved; (B) two NPH injections daily. We assessed: (i) diabetes control on monthly HbA1c levels and occurrence of hypoglycaemic events; (ii) local tolerance on clinical symptoms, rhinoscopy, nasal muco-ciliary clearance and nasal biopsies; (iii) insulin absorption at months 0 and 4.

RESULTS

One patient was withdrawn because of cough and dizziness after each nasal application. HbA1c was not significantly different at month 4 (9.4 +/- 0.5% vs. 8.8 +/- 0.2%, A vs. B). Blood glucose control remained only fair in the majority of our patients. Nasal insulin was able to replace the daytime fraction of the subcutaneous insulin with a 18% efficacy. Side-effects included transient nasal hyperactivity (pruritus, sneezing and rhinorrhoea) and chronic persistence of nasal crusts. Plasma insulin profiles were not significantly different between months 0 and 4.

CONCLUSIONS

The utilization of nasal insulin (with or without NPH) was associated with similar diabetes control compared with NPH twice daily. Nasal insulin alone was able to achieve an adequate glycaemic control in three of the 10 patients.

Evaluation of basement membrane degradation during TNF-alpha-induced increase in epithelial permeability

We evaluated whether tumor necrosis factor (TNF)-alpha induces an increase in permeability of an alveolar epithelial monolayer via gelatinase secretion and basement membrane degradation. Gelatinase secretion and epithelial permeability to radiolabeled albumin under unstimulated and TNF-alpha-stimulated conditions of an A549 human epithelial cell line were evaluated in vitro. TNF-alpha induced both upregulation of a 92-kDa gelatinolytic activity (pro form in cell supernatant and activated form in extracellular matrix) and an increase in the epithelial permeability coefficient compared with the unstimulated condition (control: 1.34 +/- 0.04 x 10(-6) cm/s; 1 microg/ml TNF-alpha: 1.47 +/- 0.05 x 10(-6) cm/s, P < 0.05). The permeability increase in the TNF-alpha-stimulated condition involved both paracellular permeability, with gap formation visualized by actin cytoskeleton staining, and basement membrane permeability, with an increase in the basement membrane permeability coefficient (determined after cell removal; control: 2.58 +/- 0.07 x 10(-6) cm/s; 1 microg/ml TNF-alpha: 2.82 +/- 0.02.10(-6) x cm/s, P < 0.05). Because addition of gelatinase inhibitors [tissue inhibitor of metalloproteinase (TIMP)-1 or BB-3103] to cell supernatants failed to inhibit the permeability increase, the gelatinase-inhibitor balance in the cellular microenvironment was further evaluated by cell culture on a radiolabeled collagen matrix. In the unstimulated condition, spontaneous collagenolytic activity inhibited by addition to the matrix of 1 microg/ml TIMP-1 or 10(-6) M BB-3103 was found. TNF-alpha failed to increase this collagenolytic activity because it was associated with dose-dependent upregulation of TIMP-1 secretion by alveolar epithelial cells. In conclusion, induction by TNF-alpha of upregulation of both the 92-kDa gelatinase and its inhibitor TIMP-1 results in maintenance of the gelatinase-inhibitor balance, indicating that basement membrane degradation does not mediate the TNF-alpha-induced increase in alveolar epithelial monolayer permeability.

Radiofrequency is a safe and effective treatment of turbinate hypertrophy

OBJECTIVE

To evaluate the safety and efficacy of radiofrequency for reduction of inferior turbinate volume.

STUDY DESIGN

Prospective before-and-after trial.

METHODS

Fourteen patients complaining of chronic nasal obstruction and failing to respond to medical treatment were prospectively enrolled. All patients presented with inferior turbinate hypertrophy and no septal deformity. Radiofrequency inferior turbinate tissue reduction with three punctures in each turbinate (mean energy/puncture: 342 +/- 36 J, mean duration: 69 +/- 17 s, plateau tissue temperature: 75 +/- 6.4 degrees C). Patients were evaluated before and on days 3, 7, and 60 after intervention.

RESULTS

No postoperative pain or complications were reported. Evaluation of nasal obstruction, quantified by visual analogue scale, showed a significant decrease of day time and nighttime obstruction after surgery. Acoustic rhinometry measurements showed that turbinate hypertrophy was significantly reduced in the sitting and supine positions on day 60 after surgery. Saccharin transit times decreased significantly on day 60 compared with preoperative measurements. Ciliary beat frequency, measured in vitro in nasal epithelial cells sampled from the inferior turbinate by brushing, was not significantly different before surgery and on day 60 after surgery. In the same samples, ciliated cells were the most abundant epithelial cell type before and after surgery, although in five cases, moderate numbers of squamous cells were detected on either day 7 or day 60 after surgery.

CONCLUSION

Radiofrequency is a safe surgical procedure capable of reducing turbinate volume without altering the nasal mucosa, and causing minimal discomfort for the patient.

Six month administration of gelified intranasal insulin in 16 type 1 diabetic patients under multiple injections: efficacy vs subcutaneous injections and local tolerance

OBJECTIVE

Nasal insulin administration is a potential route for intensive insulin management, less invasive and more rapid than subcutaneous injections. Previous studies have shown poor bioavailability (less than 15%) with nasal insulin administration with various absorption enhancers. The aim of the study was to evaluate in type 1 diabetic patients, the metabolic efficacy and local tolerance of a new gelified sprayed nasal insulin containing glychocolate and methylcellulose as absorption promoters.

MATERIAL AND METHODS

The study was conducted in 16 type 1 diabetic patients (HbA1c 8.6+/-0.2%) in a cross-over trial including 2 six month randomized periods: a) NPH twice daily + 3 pre-prandial nasal insulin doses + nasal supplementation in case of unexpected hyperglycaemia; b) NPH twice daily + 3 pre-prandial regular insulin injections. End points were HbA1c levels, hypoglycaemic episodes and tolerance evaluated at month 0, 2, 6 and 8 on clinical symptoms and objective nasal assessments.

RESULTS

Four patients were withdrawn because of nasal burning (3 cases) and persistent sinusitis (1 case), and one patient had purulent sinusitis at the month 6 examination. At month 6, HbA1c levels were comparable (8.3 +/- 0.1 vs 8.6 +/- 0.1%, m +/- SEM, NS) for nasal and subcutaneous period respectively. The number of hypoglycaemic events was identical during the 2 periods (88 episodes). Nasal tolerance with the gelified form was better than with the already reported lyophilized form but, when present, symptoms were more marked, suggesting a potentiating additional role of methylcellulose excipient on nasal intolerance.

CONCLUSIONS

1) Gelified nasal insulin is as efficient as subcutaneous regular insulin in type 1 diabetic patients. 2) Other galenic forms should be investigated to improve nasal tolerance and bioavailability.

Increased expression of matrix metalloproteinase-9 in nasal polyps

To investigate the role of gelatinases in nasal polyposis, a common and disabling airway disease characterized by chronic inflammation and tissue remodelling, matrix metalloproteinase-2 (MMP-2) and MMP-9 expression was investigated in the nasal polyps (NP) of 24 patients undergoing ethmoidectomy and compared with 15 control nasal mucosal (CM) samples obtained from snorers during turbinectomy. Tissue samples were either frozen for enzymatic analysis or paraffin wax-embedded for immunohistochemistry. Zymography and quantitative image analysis showed that MMP-9 active forms were significantly increased (p<0.05) in NPs compared to CM (44 +/- 40 versus 13 +/- 19x10(3) AU/10 microg protein), while MMP-2 expression was similar in both tissues. Concomitant studies of gelatinase immunoexpression showed that MMP-9 expression was enhanced (4- to 16-fold) in surface epithelium, glands (p<0.05), and submucosal inflammatory cells (p<0.05). In addition, MMP-9 positivity was markedly increased in endothelial cells (p<0.01). In situ zymography demonstrated marked gelatinolytic activity, consistent with the immunolocalization of MMP-2 and MMP-9. These results suggest up-regulation of active MMP-9 in the glands and vessels characteristic of NPs. It is concluded that MMP-9 may play a role in the upper airway remodelling observed during nasal polyposis.

The human dynein intermediate chain 2 gene (DNAI2): cloning, mapping, expression pattern, and evaluation as a candidate for primary ciliary dyskinesia

Primary ciliary dyskinesia (PCD) is an autosomal recessive disease characterized by chronic sinusitis and bronchiectasis, and usually associated with hypofertility. Half of the patients present a situs inversus, defining the Kartagener's syndrome. This phenotype results from axonemal abnormalities of respiratory cilia and sperm flagella, i.e., mainly an absence of dynein arms. Recently, a candidate-gene approach, based on documented abnormalities of immotile strains of Chlamydomonas reinhardtii, allowed us to identify the first gene involved in PCD. Following the same strategy, we have characterized DNAI2, a human gene related to Chlamzydomonas IC69, and evaluated its possible involvement in a PCD population characterized by an absence of outer dynein arms. DNAI2, which is composed of 14 exons located at 17q25, is highly expressed in trachea and testis. No mutation was found in the DNAI2 coding sequence of the twelve patients investigated. However, ten intragenic polymorphic sites and an EcoRI RFLP have been identified, allowing the exclusion of DNAI2 in three consanguineous families.

Relation of epidermal growth factor receptor expression to goblet cell hyperplasia in nasal polyps

BACKGROUND

Because the epidermal growth factor receptor (EGFR) system regulates mucin production in airway epithelium, we hypothesized a role for this system in mucus hypersecretion that occurs in nasal polyposis.

OBJECTIVE

We examined the relationship between goblet cell hyperplasia, EGFR expression, and inflammatory mediators produced by eosinophils and neutrophils in nasal polyp tissues.

METHODS

Nasal polyp tissue samples from 8 patients and nasal turbinate biopsy specimens from 6 normal control subjects were examined for alcian blue/PAS staining, mucin MUC5AC (MUC5AC), and EGFR immunoreactivity and EGFR gene expression (in situ hybridization). We also examined the role of eosinophils and neutrophils in goblet cell hyperplasia.

RESULTS

In control nasal mucosa alcian blue/periodic acid-Schiff- and MUC5AC-stained areas were 18.40% +/- 1.31% and 21.89% +/- 1.43%, respectively. In polyps the alcian blue/periodic acid-Schiff- and MUC5AC-stained areas were 51.30% +/- 5.85% and 52.07% +/- 6.58%, which was significantly larger than that found in control subjects (each comparison, P <.01). Four of 6 control specimens expressed EGFR messenger RNA and protein weakly in the epithelium. In polyps 4 of 8 specimens expressed EGFR gene and EGFR protein strongly; the EGFR-stained area was greater in hyperplastic than in pseudostratified epithelium. TNF-alpha immunoreactivity, expressed in eosinophils, was increased in EGFR-positive polyps compared with EGFR-negative polyps, suggesting a role for TNF-alpha in EGFR expression. Neutrophils were increased in the epithelium of EGFR-positive compared with EGFR-negative polyps, suggesting a role for these cells in mucin expression and in goblet cell degranulation.

CONCLUSION

These data suggest a role for EGFR cascade in the regulation of goblet cell mucins in nasal polyps. Proof of concept will require clinical studies using selective EGFR inhibitors.

[Implication of extracellular matrix metalloproteinases in the course of chronic inflammatory airway diseases]

Matrix metalloproteinases (MMPs) are major proteolytic enzymes that are involved in extracellular matrix (ECM) turn over. MMP-2 (gelatinase A) and MMP-9 (gelatinase B) cleave type IV collagen, which is an important constituent of basement membrane. These enzymes play an important role in normal tissue homeostasis, but imbalance between MMPs and their tissue inhibitors (TIMPs) is thought to be a critical factor in regulating tissue remodeling. MMP-2 is produced by fibroblasts, endothelial, and epithelial cells, while MMP-9 is mainly produced by inflammatory cells. The role of MMPs was investigated through biochemical analysis or in situ expression, in the pathogenesis of two chronic inflammatory airway diseases, asthma and nasal polyposis. Both are characterized with the accumulation of active inflammatory cells, matrix remodeling and epithelial changes. Increased levels of MMP-9 and TIMP-1 were found in asthmatic subjects and NP. In NP, MMP-9 expression was detected in epithelial, endothelial and inflammatory cells. In this setting, MMP-9 could play a crucial role in the transmigration of basement membrane components by inflammatory cells leading to inflammatory cell accumulation and maintenance of inflammation in airway. Moreover, MMP-9 may contribute to cell migration, an important mechanism involved in the repair of the respiratory epithelium.

Characterization of inflammatory reaction in upper airways of cystic fibrosis patients

Inflammatory cell populations have not been yet precisely evaluated in cystic fibrosis (CF) airways. We intended to characterize morphological modifications, inflammatory cell infiltration and cell proliferation in nasal tissues obtained from 15 CF patients and from 6 non-CF patients with nasal polyposis. Morphological analysis showed an intense inflammatory infiltration in CF and non-CF tissues with only few modifications in the epithelium from CF tissues. Inflammatory cell populations characterized by specific immunolabeling were quantified, showing a predominance of macrophages and T- and B-lymphocytes and only moderate numbers of neutrophils in CF tissues; in non-CF polyps, lymphocytes and eosinophils were abundant. Proliferating cell percentages quantified after proliferating cell nuclear antigen immunolabeling were 5.3+/-4.1% (mean +/- SD) in CF polyps and 3.1+/-1.2% in non-CF polyps in epithelium but were very low in lamina propria. Intense inflammation in nasal tissues from CF patients is therefore dominated by macrophages and lymphocytes rather than by neutrophils. While morphology is preserved, proliferation is high in epithelium from CF polyps. These findings should be regarded in the future for a better understanding of inflammation in CF airway disease.

Inflammatory cells as well as epithelial cells in nasal polyps express vascular endothelial growth factor

In nasal polyps (NPs), locally secreted growth factors are involved in the remodelling of the epithelium and extracellular matrix but little is known concerning vessel remodelling. The in situ expression of vascular endothelial growth factor (VEGF) in NPs and control nasal mucosa (CM) were evaluated and in vitro secretion of VEGF from primary human cultures of nasal epithelial cells (HNECs) was quantified. VEGF expression was evaluated in NP (n=14) and CM (n=6) after immunolabelling. In supernatants from HNECs cultured at air/liquid interface, VEGF was quantified by immunoassay, under baseline conditions and after transforming growth factor-beta1 (TGF-beta1) stimulation. In HNEC lysates, VEGF and VEGF messenger ribonucleic acid (mRNA) were detected using Western blot analysis and reverse transcriptase polymerase chain reaction respectively. VEGF positivity was more frequent in inflammatory cells in NPs (14 of 14) than in CM (three of six) (p<0.05) and in the epithelium in NPs (six of 14) than in CM (two of six) (nonsignificant). Under baseline conditions, the VEGF concentration in HNEC culture medium increased from day 2 to 4, then decreased and became undetectable. VEGF concentrations increased significantly after TGF-beta1 stimulation. In HNEC lysates, VEGF and VEGF mRNA were detected on days 4 and 14 of culture. It was concluded that vascular endothelial growth factor is intensely expressed in situ in nasal polyps, mainly in inflammatory cells but also in epithelial cells. Human nasal epithelial cells are able to secrete in vitro vascular endothelial growth factor. Transforming growth factor-beta1 upregulates this secretion. This suggests that vascular endothelial growth factor, inducing oedema and angiogenesis, could be involved in the pathogenesis of nasal polyps.

Loss-of-function mutations in a human gene related to Chlamydomonas reinhardtii dynein IC78 result in primary ciliary dyskinesia

Primary ciliary dyskinesia (PCD) is a group of heterogeneous disorders of unknown origin, usually inherited as an autosomal recessive trait. Its phenotype is characterized by axonemal abnormalities of respiratory cilia and sperm tails leading to bronchiectasis and sinusitis, which are sometimes associated with situs inversus (Kartagener syndrome) and male sterility. The main ciliary defect in PCD is an absence of dynein arms. We have isolated the first gene involved in PCD, using a candidate-gene approach developed on the basis of documented abnormalities of immotile strains of Chlamydomonas reinhardtii, which carry axonemal ultrastructural defects reminiscent of PCD. Taking advantage of the evolutionary conservation of genes encoding axonemal proteins, we have isolated a human sequence (DNAI1) related to IC78, a C. reinhardtii gene encoding a dynein intermediate chain in which mutations are associated with the absence of outer dynein arms. DNAI1 is highly expressed in trachea and testis and is composed of 20 exons located at 9p13-p21. Two loss-of-function mutations of DNAI1 have been identified in a patient with PCD characterized by immotile respiratory cilia lacking outer dynein arms. In addition, we excluded linkage between this gene and similar PCD phenotypes in five other affected families, providing a clear demonstration of locus heterogeneity. These data reveal the critical role of DNAI1 in the development of human axonemal structures and open up new means for identification of additional genes involved in related developmental defects.

Effect of increased pressure on tracheal ciliary beat frequency

Effects of increased ambient pressure on mucociliary clearance have been poorly investigated. The effects of increasing pressures on ciliary beat frequency (CBF) of guinea-pig tracheal rings were studied in vitro. Increased pressures of 25 and 100 kPa induced a significant and equivalent enhancement of CBF from 30 min after the pressure increase. The increase in CBF observed after a pressure increase of 50 kPa (inspiratory oxygen fraction = 21%), was significantly greater than that observed with an equivalent oxygen tension at atmospheric pressure, i.e. with a gas mixture containing 30% oxygen. Addition of N(G)-nitro-L-arginine methylester (L-NAME) inhibited the enhancement in CBF observed after the 25 kPa pressure increase. Addition of L-arginine reversed the effect of L-NAME. These results demonstrate that a pressure increase applied to tracheal rings, in vitro, induces an enhancement of ciliary beat frequency and that generation of nitric oxide may be involved in this ciliary stimulation.

Expression of the transforming growth factor beta isoforms in inflammatory cells of nasal polyps

OBJECTIVE

To determine the expression and the potential role of transforming growth factor beta (TGF-beta) in nasal polyposis.

DESIGN

Comparison of TGF-beta expression between normal and inflammatory nasal mucosa and polyps; in inflammatory nasal polyps, characterization of the TGF-beta isoforms expression and their potential location in macrophages and eosinophils.

SETTING

Patients and samples were selected at the Hôpital Intercommunal, Créteil, France, and immunohistochemistry and immunoblots were performed at the Institut National de la Sante et de la Recherche Medicale U296 (Universite Paris XII, France).

SUBJECTS

Nasal polyps and nasal mucosa were sampled in 21 patients during ethmoidectomy, and muscosa was sampled in 6 healthy patients during rhinoplasty.

METHODS

Immunohistochemistry and Western blot analysis were performed using specific antibodies to TGF-beta1-3, TGF-beta1, TGF-beta2, and TGF-beta3 isoforms. Double labeling was also performed using anti-TGF-beta1 antibody together with macrophages or eosinophil-specific antibodies.

RESULTS

The expression of TGF-beta(1-3) was significantly higher in inflammatory nasal polyps than in inflammatory nasal mucosa and higher in inflammatory nasal mucosa than in nasal mucosa from healthy patients. Transforming growth factor beta1 was the main isoform detected in inflammatory nasal polyps, and it was present in numerous macrophages and in some eosinophils.

CONCLUSIONS

Transforming growth factor beta, mainly TGF-beta1, is strongly expressed in inflammatory nasal mucosa, where it could be produced by macrophages and eosinophils. Transforming growth factor beta could induce epithelium and connective tissue modifications and therefore be involved in the pathogenesis of nasal polyposis.

Epithelial cell proliferation, apoptosis, and apoptosis inhibition in inverted papillomas

Inverted papillomas (IPs) are rare benign tumors of nasal epithelium with high recurrence rates and malignant transformation potential. Their etiology is still uncertain, and the mechanism of their growth has not yet been fully described. The purpose of this study was to detect, quantify, and compare cell proliferation, apoptosis, and apoptosis inhibition in hyperplastic epithelium from IPs and in inflammatory nasal polyps (NPs). IP samples were obtained after surgical removal of tumor in 13 patients, and NPs were sampled during endoscopic ethmoidectomy in 10 patients with nasal polyposis. Cell proliferation and apoptosis inhibition, respectively, were assessed by immunohistochemical identification of the proliferating cell nuclear antigen (PCNA) and the oncoprotein Bcl-2. Apoptosis was evaluated by analyzing the DNA fragmentation. Cell proliferation and apoptosis were significantly higher in IPs than in NPs (P = .0002 and P = .043, respectively), while apoptosis inhibition was significantly lower in IPs than in NPs (P = .001). Concerning IPs, cell proliferation was significantly higher than apoptosis (P = .0029) and apoptosis inhibition (P = .0015). The increase in epithelial cell proliferation seemed to be greater in IPs with dysplasia than in IPs without dysplasia. Increased epithelial cell proliferation, but not apoptosis and apoptosis inhibition, seems to be involved in the development of IP.

Mucin gene (MUC 2 and MUC 5AC) upregulation by Gram-positive and Gram-negative bacteria

Bacterial infection of the lung is associated with mucin overproduction. In partial explanation of this phenomenon, we recently reported that supernatant from the Gram-negative organism Pseudomonas (P.) aeruginosa contained an activity that upregulated transcription of the MUC 2 mucin gene [J.-D. Li, A. Dohrman, M. Gallup, S. Miyata, J. Gum, Y. Kim, J. Nadel, A. Prince, C. Basbaum, Transcriptional activation of mucin by P. aeruginosa lipopolysaccharide in the pathogenesis of cystic fibrosis lung disease, Proc. Natl. Acad. Sci. U.S.A., 94 (1997) 967-972]. The purpose of the present study was to determine whether mucin genes other than MUC 2 are so regulated and whether Gram-positive organisms also contain mucin stimulatory activity. Results from in situ hybridization and RNase protection assays showed that P. aeruginosa upregulates MUC 5AC as well as MUC 2 in both bronchial explants and cultured airway epithelial cells. The upregulation of both genes by P. aeruginosa can be mimicked by lipopolysaccharide (LPS) and can be blocked by the tyrosine kinase inhibitor genistein. In addition, both genes are upregulated by a variety of Gram-positive as well as Gram-negative organisms showing the same rank order of potency. These data indicate the existence of a general mechanism by which epithelial cells respond to the presence of bacteria by increasing mucin synthesis.

Results of tympanoplasty in children with primary ciliary dyskinesia

OBJECTIVE

To assess the results of tympanoplasty in children with primary ciliary dyskinesia complicated by tympanic perforation or cholesteatoma with hearing loss and/or recurrent otorrhea.

DESIGN

Retrospective study. Postoperative follow-up of 26.3 months in the type 1 tympanoplasty group and 46 months in the child with cholesteatoma.

SETTING

Hospitalized care, referral center.

PATIENTS

Seven children with primary ciliary dyskinesia, complicated in 6 children by 9 tympanic perforations (3 bilateral perforations) and in 1 child by an attical cholesteatoma.

RESULTS

After 9 type 1 tympanoplasties, the grafts were intact in 9 ears, with no recurrence of otorrhea, but serous otitis media was present in 6 of the 9 ears. Auditory improvement was significant, with an average gain of 17-dB hearing level in speech frequencies. After a canal wall-down tympanoplasty with mastoidectomy for attic cholesteatoma in 1 ear, the cavity that was operated on showed no signs of otorrhea or residual cholesteatoma after a follow-up of 46 months.

CONCLUSION

In children with primary ciliary dyskinesia, tympanoplasty has a high probability of graft success and auditory improvement, despite the frequent recurrence of serous otitis media.

Incidence of primary ciliary dyskinesia in children with recurrent respiratory diseases

The goal of the study was to evaluate the incidence of primary ciliary dyskinesia (PCD) in children suffering from recurrent respiratory tract infections (RRIs) by means of noninvasive method. Respiratory ciliated cells were collected by nasal brushing in 118 children (4.6 +/- 2.5 years) with RRIs. The ciliary beat frequency (CBF) was measured with a stroboscopic method, and when the CBF was abnormal, the ciliary ultrastructure was analyzed by a quantitative method. The CBF could be measured in 106 patients (90%) and was abnormal in 15 patients. The ciliary ultrastructure was found to be abnormal in 11 of 15 patients: PCD was diagnosed in 6 cases, and acquired ciliary defects were observed in the remaining 5 patients. Our conclusion, that PCD is rare but net exceptional (5.6%) in children with RRIs, justifies the systematic investigation of ciliated cells in such patients. For this purpose, nasal brushing can be used to sample ciliated cells even in young children.

Isolation of several human axonemal dynein heavy chain genes: genomic structure of the catalytic site, phylogenetic analysis and chromosomal assignment

Dynein heavy chains (DHCs) are the main components of multisubunit motor ATPase complexes called dyneins. Axonemal dyneins provide the driving force for ciliary and flagellar motility. Recent molecular studies demonstrated that multiple DHC isoforms are produced by separate genes. We describe the isolation of five human axonemal DHC genes. Analysis of the human genomic clones revealed the existence of intronic sequences that were used to demonstrate that human axonemal DHC genes are located on different chromosomes. The cloned human DHC sequences were integrated into an evolutionary approach based on phylogenetic analysis. Tissue expression studies showed that these human axonemal DHCs are expressed in testis and/or trachea, two tissues with axonemal structures that can be altered in primary ciliary dyskinesia, making DHC genes strong candidates in the genesis of these human diseases.

Myofibroblast accumulation induced by transforming growth factor-beta is involved in the pathogenesis of nasal polyps

Myofibroblasts that express alpha-smooth muscle actin (alpha-SMA) are detected in many chronic inflammatory diseases. Transforming growth factor-beta (TGF-beta) is a potent inducer of myofibroblast accumulation in tissues. In this study, scattered myofibroblasts and TGF-beta were quantified and localized in nasal polyps (NPs) and normal nasal mucosa (NM). NPs were sampled in 16 patients during ethmoidectomy and NM was obtained from 10 control subjects during rhinoplasty. alpha-SMA and TGF-beta were detected using immunohistochemistry and the numbers of labeled cells were quantified (alpha-SMA and TGF-beta indices) and compared between NPs and NM. In eight NPs, in which the pedicle was preserved, alpha-SMA and TGF-beta were evaluated and compared in the pedicle, central, and tip areas. Finally, TGF-beta expression was compared between low (zone 1), moderate (zone 2), and high (zone 3) zones of alpha-SMA positivity. alpha-SMA and TGF-beta indices were significantly higher in NPs than in NM. In the eight selected NPs, alpha-SMA-positive cells were significantly more abundant in the pedicle than in the central and tip areas, whereas TGF-beta-positive cells were significantly more numerous in the pedicle than in the tip area. The number of TGF-beta-positive cells was significantly higher in zone 3 than in zone 1 of alpha-SMA positivity. Myofibroblasts, which are abundant in NPs but rare in NM, could be involved in the growth of NPs by inducing extracellular matrix accumulation. The local development of myofibroblasts in NPs could be controlled by TGF-beta, locally produced by inflammatory cells.

Modified epithelial cell distribution in chronic airways inflammation

Although airway epithelium is known to be modified during chronic respiratory diseases, epithelial cells have rarely been precisely quantified. We therefore intended to evaluate epithelial cell distribution in inflammatory airways, using a cytological approach. Nasal airway cells in 12 patients with nonallergic chronic rhinitis were sampled by brushing, quantified after cytocentrifugation and compared to those from eight controls. Cell populations were quantified after May-Grünwald Giemsa staining and alpha-tubulin immunolabelling to demonstrate ciliary differentiation. When compared to controls, rhinitis patients exhibited lower percentages of ciliated cells (59 +/- 4 versus 32 +/- 2%, respectively), and higher percentages of goblet (24 +/- 3 versus 37 +/- 2%) and basal cells (9 +/- 1 versus 18 +/- 2%). After tubulin immunolabelling, positive staining was specifically detected in cells with cilia (LC+), and in the cytoplasm of some small round cells without obvious cilia (LC-). Fewer immunolabelled cells were detected in rhinitis patients than in controls (with significantly lower percentages of LC+ and higher percentages of LC-). Nasal brushing is an effective technique for quantification of airway epithelial cells. Tubulin immunolabelling is useful to detect ciliated cells and distinguishes another cell population, possibly preciliated cells. These cytological findings suggest the presence of modifications of epithelial differentiation and proliferation, possibly related to local chronic inflammation.

Airway epithelial damage induced by sulfur mustard in guinea pigs, effects of glucocorticoids

Sulfur mustard (SM) represents a potential chemical warfare agent. In order to characterize SM-induced airway epithelial damage, we studied the effects of an intratracheal injection of 0.3 mg/kg of SM in guinea pigs, 5 h, 24 h, 14 days and 35 days after exposure. During the acute period, lesions prevailed in tracheal epithelium exhibiting intra-epithelial blisters, inflammatory cell infiltration and columnar cell shedding with exposure of basal cells. Fourteen days after intoxication, tracheal epithelium appeared disorganized and showed a significant decrease in height and cell density. Tracheal epithelium recovery was still not complete even 35 days after SM-intoxication. At day 14, in SM-intoxicated guinea pigs treated with betamethasone from day 7 to day 14, epithelium height, cell density and cell proliferation (evaluated by immunohistochemistry) were significantly increased compared to untreated guinea pigs. In conclusion, the lesions observed in SM-intoxicated guinea pigs seem to be in accordance with clinical human observations and are relevant to the study of airway epithelial damage induced by SM. This animal model could be used to illustrate tracheal epithelium regeneration mainly derived from basal cells and to show glucocorticoid effects on airway epithelial recovery after chemical aggression.

Secondary alveolar proteinosis in cancer patients

Pulmonary alveolar proteinosis (AP) is a rare cause of progressive respiratory failure in the normal host. It was first described by Rosen and coworkers in 1958 on the morphological basis of the accumulation of a PAS-positive material in the alveolar space. A couple of years later, AP was found to be unexpectedly associated with malignant diseases, especially with acute or chronic myeloid leukemias. These forms were called secondary AP in opposition to the primary forms observed in normal hosts. Probably because of its morphological definition and late diagnosis by means of histology or autopsy material, secondary AP has been considered to be life-threatening for a long time. However, recent observations show that AP can be diagnosed early in the course of the disease, especially through bronchoalveolar lavage, as long as the pathologist is aware of this possibility. Another point is that secondary AP can be reversible, both clinically and morphologically. This article summarizes the clinical features, morphological findings, and the main malignant diseases associated with secondary AP. We also comment on the hypotheses proposed in the literature to explain the association of AP, malignant disease, and immunosuppression. Alveolar macrophage is likely a key factor in the occurrence of secondary AP.

Nasal polyposis pathogenesis: a flow cytometric and immunohistochemical study of epithelial cell proliferation

In nasal polyps, constantly associated with chronic inflammation, frequent epithelial morphological changes (squamous metaplasia, secretory hyperplasia) suggest a dysregulation of epithelial cell proliferation. Cell proliferation in nasal respiratory epithelium was therefore evaluated in nasal polyposis. In 20 patients, we compared cell proliferation in mucosa from the inferior turbinate to these in nasal polyps using two methods: Flow cytometry analyzing first the ploidy and the percentage of S-phase cells (propidium iodide DNA labeling), secondly the percentage of Ki-67-labeled cells and the green fluorescent index (fluorescein-conjugated anti-human Ki-67 antigen labeling, and thirdly the percentage of Ki-67-labeled cells being in S-phase. Immunohistochemistry, quantifying the expression of Ki-67 antigen in the epithelium permitting to calculate a Ki-67 index. All cell-populations studied were diploid. Percentages of S-phase cells, Ki-67-labeled cells, Ki-67 labeled cells being in the S-phase and green fluorescence index was significantly higher in nasal polyps than in mucosa Ki-67 index were significantly higher in nasal polyps than in mucosa in the epithelium. Epithelial cell proliferation which is therefore increased in nasal polyp could play an important role in nasal polyposis pathogenesis and its relationships with inflammation can be suggested.

Epithelial cell proliferation in nasal polyps could be up-regulated by platelet-derived growth factor

The modifications of epithelial differentiation and proliferation observed in nasal polyps (NP) could be related to local secretion of growth factors, among which platelet-derived growth factor (PDGF) could play a key role. We therefore prospectively studied, by immunohistochemistry, proliferating cell nuclear antigen (PCNA, an S-phase cell marker), PDGF, and CD-68 (activated macrophages marker) expression in NP and inferior turbinate mucosa (NM) in 11 patients. Our data show that PCNA and PDGF expression are increased in NP epithelium, while CD-68 expression is increased in NP epithelium and lamina propria when compared to NM. Increased local PDGF secretion by numerous activated macrophages could therefore be involved in epithelial cell proliferation up-regulation in NP. PDGF could also be involved in the pathogenesis of NP via its connective tissue remodeling actions.

Bronchoalveolar lavage in adult sickle cell patients with acute chest syndrome: value for diagnostic assessment of fat embolism

Fat embolism of necrotic bone marrow could be a frequent cause of acute chest syndrome (ACS) in sickle cell syndromes (SC), as suggested by postmortem findings. To check this hypothesis in living patients, we evaluated the presence of fatty macrophages recovered by bronchoalveolar lavage (BAL) in ACS. We investigated 20 consecutive cases of ACS by BAL, and identification of alveolar cells containing fat droplets was performed using oil red O (ORO), a specific neutral fat stain. The specificity of the method was determined on control groups, including eight SC patients without acute chest syndrome and 15 non-SC patients. A cut-off of > 5% of alveolar macrophages containing fat droplets was determined from the control groups to assess the diagnosis of fat embolism. In 12 ACS episodes, BAL exhibited > 5% of fatty macrophages, ranging from 10% to 100% (median value 46.5%). In 11 cases, fat embolism was associated with proven (n = 8) or probable (n = 3) bone marrow infraction, which mostly predated ACS. Eight ACS episodes were associated with a low percentage (< or = 5%) of fatty alveolar macrophages and could be related to a cause other than fat embolism in six episodes, such as sepsis, in-situ thrombosis, or rib infarcts generating hypoventilation. This study supports the diagnostic yield of BAL for fat embolism, which can be incriminated in 60% of cases of ACS in this adult population.