Teratoma of the nasal septum in a neonate: an endoscopic approach

Initial presentation of a white female newborn delivered after normal pregnancy demonstrated a white mass obstructing the left nare. Primary biopsy revealed a focus of fibrotic nasal mucosa that included squamous and respiratory epithelium. After endoscopic resection of the mass, histopathologic examination resulted in the diagnosis of a teratoma. According to our literature review, this is the first case of a teratoma arising from the nasal septum in a white. Worldwide, 3 additional cases have been reported, but none included endoscopic management. This case illustrates our protocol for an endoscopic approach to an obstructive nasal mass in a neonate and our experience in the management of this rare disease.

Molecular epidemiology of the nasal colonization by methicillin-susceptible Staphylococcus aureus in Swiss children

Nasal carriage of Staphylococcus aureus contributes to an increased risk of developing an infection with the same bacterial strain. Genetic regulatory elements and toxin-expressing genes are virulence factors associated with the pathogenic potential of S. aureus. We undertook an extensive molecular characterization of methicillin-susceptible S. aureus (MSSA) carried by children. MSSA were recovered from the nostrils of children. The presence of Panton-Valentine leukocidin (PVL), exfoliatins A and B (exfoA and exfoB), and the toxic-shock staphylococcal toxin (TSST-1) and agr group typing were determined by quantitative PCR. A multiple-locus variable-number of tandem repeat analysis (MLVA) assay was also performed for genotyping. Five hundred and seventy-two strains of MSSA were analysed. Overall, 30% were positive for toxin-expressing genes: 29% contained one toxin and 1.6% two toxins. The most commonly detected toxin gene was tst, which was present in 145 (25%) strains. The TSST-1 gene was significantly associated with the agr group 3 (OR 56.8, 95% CI 32.0-100.8). MLVA analysis revealed a large diversity of genetic content and no clonal relationship was demonstrated among the analysed MSSA strains. Multilocus sequence typing confirmed this observation of diversity and identified ST45 as a frequent colonizer. This broad diversity in MSSA carriage strains suggests a limited selection pressure in our geographical area.

Expansive nasopalatine duct cysts with nasal involvement mimicking apical lesions of endodontic origin: a report of two cases

The nasopalatine duct cyst (NPDC) is the most frequent nonodontogenic cyst of the jaws and can be misinterpreted as an apical lesion of endodontic origin.

Microfluidic wound-healing assay to assess the regenerative effect of HGF on wounded alveolar epithelium

We present a microfluidic epithelial wound-healing assay that allows characterization of the effect of hepatocyte growth factor (HGF) on the regeneration of alveolar epithelium using a flow-focusing technique to create a regular wound in the epithelial monolayer. The phenotype of the epithelial cell was characterized using immunostaining for tight junction (TJ) proteins and transmission electron micrographs (TEMs) of cells cultured in the microfluidic system, a technique that is reported here for the first time. We demonstrate that alveolar epithelial cells cultured in a microfluidic environment preserve their phenotype before and after wounding. In addition, we report a wound-healing benefit induced by addition of HGF to the cell culture medium (19.2 vs. 13.5 μm h(-1) healing rate).

Crosstalk between B lymphocytes, microbiota and the intestinal epithelium governs immunity versus metabolism in the gut

Using a systems biology approach, we discovered and dissected a three-way interaction between the immune system, the intestinal epithelium and the microbiota. We found that, in the absence of B cells, or of IgA, and in the presence of the microbiota, the intestinal epithelium launches its own protective mechanisms, upregulating interferon-inducible immune response pathways and simultaneously repressing Gata4-related metabolic functions. This shift in intestinal function leads to lipid malabsorption and decreased deposition of body fat. Network analysis revealed the presence of two interconnected epithelial-cell gene networks, one governing lipid metabolism and another regulating immunity, that were inversely expressed. Gene expression patterns in gut biopsies from individuals with common variable immunodeficiency or with HIV infection and intestinal malabsorption were very similar to those of the B cell-deficient mice, providing a possible explanation for a longstanding enigmatic association between immunodeficiency and defective lipid absorption in humans.

The airway epithelium: soldier in the fight against respiratory viruses

The airway epithelium acts as a frontline defense against respiratory viruses, not only as a physical barrier and through the mucociliary apparatus but also through its immunological functions. It initiates multiple innate and adaptive immune mechanisms which are crucial for efficient antiviral responses. The interaction between respiratory viruses and airway epithelial cells results in production of antiviral substances, including type I and III interferons, lactoferrin, β-defensins, and nitric oxide, and also in production of cytokines and chemokines, which recruit inflammatory cells and influence adaptive immunity. These defense mechanisms usually result in rapid virus clearance. However, respiratory viruses elaborate strategies to evade antiviral mechanisms and immune responses. They may disrupt epithelial integrity through cytotoxic effects, increasing paracellular permeability and damaging epithelial repair mechanisms. In addition, they can interfere with immune responses by blocking interferon pathways and by subverting protective inflammatory responses toward detrimental ones. Finally, by inducing overt mucus secretion and mucostasis and by paving the way for bacterial infections, they favor lung damage and further impair host antiviral mechanisms.

Orofacial dyskinesia induced by nasal Ritalin(R) (methylphenidate) sniffing: A rare case report from Switzerland

Ritalin® (methylphenidate) is an amphetamine-like prescription stimulant commonly used in the treatment of attention deficit hyperactivity disorder in children and adults. Recently, the recreational use of Ritalin has increased, particularly among young adults. Well-known symptoms of intoxication include signs of sympathetic nervous stimulation, such as agitation, anxiety, tachycardia, hypertension, headache, tremor, and dizziness. This case report describes oral dyskinesia as a rare presentation of Ritalin intoxication, with the review of pathophysiology and some epidemiological data.

Intraperitoneal and intra-nasal vaccination of mice with three distinct recombinant Neospora caninum antigens results in differential effects with regard to protection against experimental challenge with Neospora caninum tachyzoites

Recombinant NcPDI(recNcPDI), NcROP2(recNcROP2), and NcMAG1(recNcMAG1) were expressed in Escherichia coli and purified, and evaluated as potential vaccine candidates by employing the C57Bl/6 mouse cerebral infection model. Intraperitoneal application of these proteins suspended in saponin adjuvants lead to protection against disease in 50% and 70% of mice vaccinated with recNcMAG1 and recNcROP2, respectively, while only 20% of mice vaccinated with recNcPDI remained without clinical signs. In contrast, a 90% protection rate was achieved following intra-nasal vaccination with recNcPDI emulsified in cholera toxin. Only 1 mouse vaccinated intra-nasally with recNcMAG1 survived the challenge infection, and protection achieved with intra-nasally applied recNcROP2 was at 60%. Determination of cerebral parasite burdens by real-time PCR showed that these were significantly reduced only in recNcROP2-vaccinated animals (following intraperitoneal and intra-nasal application) and in recNcPDI-vaccinated mice (intra-nasal application only). Quantification of viable tachyzoites in brain tissue of intra-nasally vaccinated mice showed that immunization with recNcPDI resulted in significantly decreased numbers of live parasites. These data show that, besides the nature of the antigen, the protective effect of vaccination also depends largely on the route of antigen delivery. In the case of recNcPDI, the intra-nasal route provides a platform to generate a highly protective immune response.

Lack of an exaggerated inflammatory response on virus infection in cystic fibrosis

Respiratory virus infections play an important role in cystic fibrosis (CF) exacerbations, but underlying pathophysiological mechanisms are poorly understood. We aimed to assess whether an exaggerated inflammatory response of the airway epithelium on virus infection could explain the increased susceptibility of CF patients towards respiratory viruses. We used primary bronchial and nasal epithelial cells obtained from 24 healthy control subjects and 18 CF patients. IL-6, IL-8/CXCL8, IP-10/CXCL10, MCP-1/CCL2, RANTES/CCL5 and GRO-α/CXCL1 levels in supernatants and mRNA expression in cell lysates were measured before and after infection with rhinoviruses (RV-16 and RV-1B) and RSV. Cytotoxicity was assessed by lactate dehydrogenate assay and flow cytometry. All viruses induced strong cytokine release in both control and CF cells. The inflammatory response on virus infection was heterogeneous and depended on cell type and virus used, but was not increased in CF compared with control cells. On the contrary, there was a marked trend towards lower cytokine production associated with increased cell death in CF cells. An exaggerated inflammatory response to virus infection in bronchial epithelial cells does not explain the increased respiratory morbidity after virus infection in CF patients.

Amphotericin B nasal spray has no effect on nasal polyps

Nasal polyps and chronic rhinosinusitis are the products of an inflammatory process. Recently, fungal involvement has been thought to stimulate the development of polyps, and administration of antifungal agents was therefore considered a potential treatment. Several studies have been published indicating amphotericin B as an effective treatment for nasal polyps and chronic rhinosinusitis. The aim of our investigation was to evaluate the efficacy of intranasal applied amphotericin B on the growth of nasal polyps in a three-month, prospective, open trial. Our results show that nasal amphotericin B spray is not effective for nasal polyps and may even cause deterioration.

Association between sleep apnea severity and blood coagulability: Treatment effects of nasal continuous positive airway pressure

A prothrombotic state may contribute to the elevated cardiovascular risk in patients with obstructive sleep apnea (OSA). We investigated the relationship between apnea severity and hemostasis factors and effect of continuous positive airway pressure (CPAP) treatment on hemostatic activity. We performed full overnight polysomnography in 44 OSA patients (mean age 47+/-10 years), yielding apnea-hypopnea index (AHI) and mean nighttime oxyhemoglobin saturation (SpO2) as indices of apnea severity. For treatment, subjects were double-blind randomized to 2 weeks of either therapeutic CPAP (n = 18), 3 l/min supplemental nocturnal oxygen (n = 16) or placebo-CPAP (<1 cm H2O) (n = 10). Levels of von Willebrand factor antigen (VWF:Ag), soluble tissue factor (sTF), D-dimer, and plasminogen activator inhibitor (PAI)-1 antigen were measured in plasma pre- and posttreatment. Before treatment, PAI-1 was significantly correlated with AHI (r = 0.47, p = 0.001) and mean nighttime SpO2 (r = -0.32, p = 0.035), but these OSA measures were not significantly related with VWF:Ag, sTF, and D-dimer. AHI was a significant predictor of PAI-1 (R2 = 0.219, standardized beta = 0.47, p = 0.001), independent of mean nighttime SpO2, body mass index (BMI), and age. A weak time-by-treatment interaction for PAI-1 was observed (p = 0.041), even after adjusting for age, BMI, pre-treatment AHI, and mean SpO2 (p = 0.046). Post hoc analyses suggested that only CPAP treatment was associated with a decrease in PAI-1 (p = 0.039); there were no changes in VWF:Ag, sTF, and D-dimer associated with treatment with placebo-CPAP or with nocturnal oxygen. Apnea severity may be associated with impairment in the fibrinolytic capacity. To the extent that our sample size was limited, the observation that CPAP treatment led to a decrease in PAI-1 in OSA must be regarded as tentative.

Galectin-3 modulates T cell activity and is reduced in the inflamed intestinal epithelium in IBD

BACKGROUND: Galectins are involved at different stages in inflammation. Galectin-3, although mostly described as proinflammatory, can also act as an immunomodulator by inducing apoptosis in T cells. The present study aims to determine galectin-3 expression in the normal and inflamed intestinal mucosa and to define its role in T cell activity. MATERIALS AND METHODS: Galectin-3 was detected by quantitative polymerase chain reaction with total RNA from endoscopic biopsies and by immunohistochemistry. Biopsies and peripheral blood mononuclear cells (PBMC) were stimulated in vitro and were used to assess the functional consequences of inhibition or exogenous addition of galectin-3. RESULTS: Galectin-3 is expressed at comparable levels in controls and inflammatory bowel disease (IBD) patients in remission. In the normal mucosa, galectin-3 protein was mainly observed in differentiated enterocytes, preferentially at the basolateral side. However, galectin-3 was significantly downregulated in inflamed biopsies from IBD patients. Ex vivo stimulation of uninflamed biopsies with tumor necrosis factor led to similar galectin-3 messenger RNA downregulation as in vivo. When peripheral blood mononuclear cells (PBMC) were analyzed, galectin-3 was mainly produced by monocytes. Upon mitogen stimulation, we observed increased proliferation and decreased activation-induced cell death of peripheral blood T cells in the presence of galectin-3-specific small interfering RNA. In contrast, exogenous addition of recombinant galectin-3 led to reduced proliferation of mitogen-stimulated peripheral blood T cells. CONCLUSIONS: Our results suggest that downregulation of epithelial galectin-3 in the inflamed mucosa reflects a normal immunological consequence, whereas under noninflammatory conditions, its constitutive expression may help to prevent inappropriate immune responses against commensal bacteria or food compounds. Therefore, galectin-3 may prove valuable for manipulating disease activity.

CD40 ligation protects bronchial epithelium against oxidant-induced caspase-independent cell death

CD40 and its ligand regulate pleiotropic biological responses, including cell proliferation, differentiation, and apoptosis. In many inflammatory lung diseases, tissue damage by environmental or endogenous oxidants plays a major role in disease pathogenesis. As the epithelial barrier is a major target for these oxidants, we postulated that CD40, the expression of which is increased in asthma, plays a role in the regulation of apoptosis of bronchial epithelial cells exposed to oxidants. Using 16HBE 14o- cells exposed to oxidant stress, we found that ligation of CD40 (induced by G28-5 monoclonal antibodies) enhanced cell survival and increased the number of cells in G2/M (interphase between DNA synthesis and mitosis) of the cell cycle. This was associated with NF-kappaB and activator protein-1 activation and increased expression of the inhibitor of apoptosis, c-IAP1. However, oxidant stress-induced apoptosis was found to be caspase- and calpain-independent implicating CD40 ligation as a regulator of caspase-independent cell death. This was confirmed by the demonstration that CD40 ligation prevented mitochondrial release and nuclear translocation of apoptosis inducing factor. In conclusion, we demonstrate a novel role for CD40 as a regulator of epithelial cell survival against oxidant stress. Furthermore, we have identified, for the first time, an endogenous inhibitory pathway of caspase-independent cell death.

Systemically transferred hematopoietic stem cells home to the subretinal space and express RPE-65 in a mouse model of retinal pigment epithelium damage

Stem cell regeneration of damaged tissue has recently been reported in many different organs. Since the loss of retinal pigment epithelium (RPE) in the eye is associated with a major cause of visual loss - specifically, age-related macular degeneration - we investigated whether hematopoietic stem cells (HSC) given systemically can home to the damaged subretinal space and express markers of RPE lineage. Green fluorescent protein (GFP) cells of bone marrow origin were used in a sodium iodate (NaIO(3)) model of RPE damage in the mouse. The optimal time for adoptive transfer of bone marrow-derived stem cells relative to the time of injury and the optimal cell type [whole bone marrow, mobilized peripheral blood, HSC, facilitating cells (FC)] were determined by counting the number of GFP(+) cells in whole eye flat mounts. Immunocytochemistry was performed to identify the bone marrow origin of the cells in the RPE using antibodies for CD45, Sca-1, and c-kit, as well as the expression of the RPE-specific marker, RPE-65. The time at which bone marrow-derived cells were adoptively transferred relative to the time of NaIO(3) injection did not significantly influence the number of cells that homed to the subretinal space. At both one and two weeks after intravenous (i.v.) injection, GFP(+) cells of bone marrow origin were observed in the damaged subretinal space, at sites of RPE loss, but not in the normal subretinal space. The combined transplantation of HSC+FC cells appeared to favor the survival of the homed stem cells at two weeks, and RPE-65 was expressed by adoptively transferred HSC by four weeks. We have shown that systemically injected HSC homed to the subretinal space in the presence of RPE damage and that FC promoted survival of these cells. Furthermore, the RPE-specific marker RPE-65 was expressed on adoptively transferred HSC in the denuded areas.

Retinal pigment epithelium damage enhances expression of chemoattractants and migration of bone marrow-derived stem cells

PURPOSE: To characterize chemoattractants expressed by the retinal pigment epithelium (RPE) after sodium iodate (NaIO3)-induced damage and to investigate whether ocular-committed stem cells preexist in the bone marrow (BM) and migrate in response to the chemoattractive signals expressed by the damaged RPE. METHODS: C57/BL6 mice were treated with a single intravenous injection of NaIO3 (50 mg/kg) to create RPE damage. At different time points real-time RT-PCR, ELISA, and immunohistochemistry were used to identify chemoattractants secreted in the subretinal space. Conditioned medium from NaIO3-treated mouse RPE was used in an in vitro assay to assess chemotaxis of stem cell antigen-1 positive (Sca-1+) BM mononuclear cells (MNCs). The expression of early ocular markers (MITF, Pax-6, Six-3, Otx) in migrated cells and in MNCs isolated from granulocyte colony-stimulating factor (G-CSF) and Flt3 ligand (FL)-mobilized and nonmobilized peripheral blood (PB) was analyzed by real-time RT-PCR. RESULTS: mRNA for stromal cell-derived factor-1 (SDF-1), C3, hepatocyte growth factor (HGF), and leukemia inhibitory factor (LIF) was significantly increased, and higher SDF-1 and C3 protein secretion from the RPE was found after NaIO3 treatment. A higher number of BMMNCs expressing early ocular markers migrated to conditioned medium from damaged retina. There was also increased expression of early ocular markers in PBMNCs after mobilization. CONCLUSIONS: Damaged RPE secretes cytokines that have been shown to serve as chemoattractants for BM-derived stem cells (BMSCs). Retina-committed stem cells appear to reside in the BM and can be mobilized into the PB by G-CSF and FL. These stem cells may have the potential to serve as an endogenous source for tissue regeneration after RPE damage.