γ-Amino butyric acid (GABA) release in the ciliated protozoon Paramecium occurs by neuronal-like exocytosis

Paramecium primaurelia expresses a significant amount of γ-amino butyric acid (GABA). Paramecia possess both glutamate decarboxylase (GAD)-like and vesicular GABA transporter (vGAT)-like proteins, indicating the ability to synthesize GABA from glutamate and to transport GABA into vesicles. Using antibodies raised against mammalian GAD and vGAT, bands with an apparent molecular weight of about 67 kDa and 57 kDa were detected. The presence of these bands indicated a similarity between the proteins in Paramecium and in mammals. VAMP, syntaxin and SNAP, putative proteins of the release machinery that form the so-called SNARE complex, are present in Paramecium. Most VAMP, syntaxin and SNAP fluorescence is localized in spots that vary in size and density and are primarily distributed near the plasma membrane. Antibodies raised against mammal VAMP-3, sintaxin-1 or SNAP-25 revealed protein immunoblot bands having molecular weights consistent with those observed in mammals. Moreover, P. primaurelia spontaneously releases GABA into the environment, and this neurotransmitter release significantly increases after membrane depolarization. The depolarization-induced GABA release was strongly reduced not only in the absence of extracellular Ca2+ but also by pre-incubation with bafilomycin A1 or with botulinum toxin C1 serotype. It can be concluded that GABA occurs in Paramecium, where it is probably stored in vesicles capable of fusion with the cell membrane; accordingly, GABA can be released from Paramecium by stimulus-induced, neuronal-like exocytotic mechanisms.

Topical oropharyngeal vancomycin to control methicillin-resistant Staphylococcus aureus lower airway infection in ventilated patients

AIM

Topical vancomycin applied to the oropharynx has been shown to control carriage and lower airway infection due to methicillin-resistant Staphylococcus aureus (MRSA). We undertook a three-year prospective observational study to evaluate the effectiveness of two policies for topical vancomycin administration on oropharyngeal carriage and lower airway infection due to MRSA in patients requiring mechanical ventilation.

METHODS

All consecutive patients aged over 18 years and expected to require mechanical ventilation for more than 72 hours were enrolled. During period one, patients who were established MRSA carriers received 1 g of 4% vancomycin gel into the oropharynx four times a day until carriage was abolished. During period two, all enrolled patients received the same protocol immediately on admission, irrespective of their MRSA carrier state.

RESULTS

One hundred ninety-one patients met the entry criteria (98 in period one and 93 in period two). During period one, 40 patients developed oropharyngeal MRSA carriage; of these, 29 acquired MRSA in the unit. In contrast, MRSA carriage was not demonstrated during period two (relative risk [RR] 0.018, 95% confidence interval [CI] 0-0.29; P=0.004). Twenty-one patients from period one suffered from an Intensive Care Unit-acquired lower airway infection due to MRSA, compared with five patients from period two (RR 0.25, 95% CI 0.10-0.64, P=0.004). Vancomycin-intermediate Staphylococcus aureus and vancomycin-resistant enterococci were not isolated.

CONCLUSION

In the setting of MRSA endemicity, the prevention of MRSA carriage by topical oropharyngeal vancomycin was more effective in reducing carriage and infection of the lower airways than treatment of established carriers.

Airway responses to methacholine and exercise at high altitude in healthy lowlanders

Peribronchial edema has been proposed as a mechanism enhancing airway responses to constrictor stimuli. Acute exposure to altitude in nonacclimatized lowlanders leads to subclinical interstitial pulmonary edema that lasts for several days after ascent, as suggested by changes in lung mechanics. We, therefore, investigated whether changes in lung mechanics consistent with fluid accumulation at high altitude within the lungs are associated with changes in airway responses to methacholine or exercise. Fourteen healthy subjects were studied at 4,559 and at 120 m above sea level. At high altitude, both static and dynamic lung compliances and respiratory reactance at 5 Hz significantly decreased, suggestive of interstitial pulmonary edema. Resting minute ventilation significantly increased by ∼30%. Compared with sea level, inhalation of methacholine at high altitude caused a similar reduction of partial forced expiratory flow but less reduction of maximal forced expiratory flow, less increments of pulmonary resistance and respiratory resistance at 5 Hz, and similar effects of deep breath on pulmonary and respiratory resistance. During maximal incremental exercise at high altitude, partial forced expiratory flow gradually increased with the increase in minute ventilation similarly to sea level but both achieved higher values at peak exercise. In conclusion, airway responsiveness to methacholine at high altitude is well preserved despite the occurrence of interstitial pulmonary edema. We suggest that this may be the result of the increase in resting minute ventilation opposing the effects and/or the development of airway smooth muscle force, reduced gas density, and well preserved airway-to-parenchyma interdependence.

Bronchodilator effects of exercise hyperpnea and albuterol in mild-to-moderate asthma

In asthmatic patients, either bronchodilatation or bronchoconstriction may develop during exercise. In 18 patients with mild-to-moderate asthma, we conducted two studies with the aims to 1) quantify the bronchodilator effect of hyperpnea induced by incremental-load maximum exercise compared with effects of inhaled albuterol (study 1, n=10) and 2) determine the time course of changes in airway caliber during prolonged constant-load exercise (study 2, n=8). In both studies, it was also investigated whether the bronchodilator effects of exercise hyperpnea and albuterol are additive. Changes in airway caliber were measured by changes in partial forced expiratory flow. In study 1, incremental-load exercise was associated with a bronchodilatation that was approximately 60% of the maximal bronchodilatation obtainable with 1,500 microg of albuterol. In study 2, constant-load exercise was associated with an initial moderate bronchodilatation and a late airway renarrowing. In both studies, premedication with inhaled albuterol (400 microg) promoted sustained bronchodilatation during exercise, which was additive to that caused by exercise hyperpnea. In conclusion, in mild-to-moderate asthmatic individuals, hyperpnea at peak exercise was associated with a potent yet not complete bronchodilatation. During constant-load exercise, a transient bronchodilatation was followed by airway renarrowing, suggesting prevalence of constrictor over dilator effects of hyperpnea. Finally, the bronchodilator effect of hyperpnea was additive to that of albuterol.

MBL2 and MASP2 gene polymorphisms in patients with hepatocellular carcinoma

The pathogenesis of hepatocellular carcinoma (HCC) is not fully understood, but the majority of patients with HCC are associated with hepatitis B virus (HBV) or hepatitis C virus (HCV) infection. Mannan-binding lectin (MBL) is a collectin that can act directly as opsonine or activate MBL-associated serine proteases (MASPs) thus initiating the antibody-independent pathway of the complement system. In our study, we analysed two MBL2 and MASP2 functional polymorphisms (MBL2 allele A/0 and MASP2 D120G) as well as MASP2 polymorphism (Y371D) responsible for an amino acidic change in the protein in 215 HCC patients (HBV-infected, HCV-infected, HBV/HCV co-infected and patients with HCC with no viral infection) and 164 healthy controls to give new insights regarding the role of these two molecules in HCC and viral infection pathogenesis. No significant association was found between MBL2 or MASP2 alleles or genotypes, neither comparing the total patients with HCC and healthy controls nor between the different groups of HCC subjects divided for type of viral infection. Also, dividing the total HCC patients group into low MBL producer (A0 and 00 genotypes) and normal producer (AA genotype) and comparing MASP2 polymorphisms in these two groups, no significant differences were found. Our data do not seem to suggest a role for MBL2 and MASP2 polymorphisms in HCC susceptibility either for HBV-HCV infection-dependent HCC or for HCC raised as a consequence of exposure to different risk factors.

The expression of innate immunity genes in Italian Crohn disease patients

Crohn' disease (CD) is a chronic idiopathic inflammatory bowel disease characterized by the interaction of both hereditary and environmental factors. Intestinal flora and pathogens such as bacteria, viruses and fungi, are thought to be the first step leading to an inflammatory status, which is subsequently amplified in genetically susceptible patients thus triggering the disease. Since the innate immune system is believed to be very important in regulating the flora of the gastrointestinal tract, we decided to study the influence of two important molecules of the innate immune system in CD. Frozen intestinal biopsies from 49 Crohn patients and 10 healthy individuals were collected at the gastroenterology unit of Children's Hospital Burlo Garofolo in Trieste and innate immunity gene expression was evaluated by using both in situ RT-PCR and quantitative PCR. We have analyzed the expression and localization of both MBL2 and DEFB1 genes in intestinal biopsies of Italian Crohn patients by in situ RT-PCR and quantitative PCR. DEFB1 is expressed equally in all subjects. Importantly, MBL2 transcripts were upregulated in CD patients compared to healthy controls. MBL2 expression in controls is normally extremely low, detectable only by quantitative PCR with a Taqman probe. We demonstrated the MBL2 and DEFB1 expression in intestinal biopsies of patients suffering from CD. Our results showed that the MBL2 gene is expressed by cells in the basal lamina, whilst DEFB1 is expressed by epithelial cells.

Selective decontamination of the digestive tract reduces bacterial bloodstream infection and mortality in critically ill patients. Systematic review of randomized, controlled trials

A systematic review and meta-analysis of randomized controlled trials (RCTs) of selective decontamination of the digestive tract (SDD) was undertaken to evaluate the impact of this procedure on bacterial bloodstream infection and mortality. Data sources were Medline, Embase, Cochrane Register of Controlled Trials, previous meta-analyses, and conference proceedings, without restriction of language or publication status. RCTs were retrieved that compared oropharyngeal and/or intestinal administration of antibiotics as part of the SDD protocol, with or without a parenteral component, with no treatment or placebo in the controls. The three outcome measures were patients with bloodstream infection, causative micro-organisms, and total mortality. Fifty-one RCTs conducted between 1987 and 2005, comprising 8065 critically ill patients were included in the review; 4079 patients received SDD and 3986 were controls. SDD significantly reduced overall bloodstream infections [odds ratio (OR), 0.73; 95% confidence interval (CI), 0.59-0.90; P=0.0036], gram-negative bloodstream infections (OR, 0.39; 95% CI, 0.24-0.63; P<0.001) and overall mortality (OR, 0.80; 95% CI, 0.69-0.94; P=0.0064), without affecting gram-positive bloodstream infections (OR, 1.06; 95% CI, 0.77-1.47). The subgroup analysis showed an even larger impact of SDD using parenteral and enteral antimicrobials on overall bloodstream infections, bloodstream infections due to gram-negative bacteria and overall mortality with ORs of 0.63 (95% CI, 0.46-0.87; P=0.005), 0.30 (95% CI, 0.16-0.56; P<0.001), and 0.74 (95% CI, 0.61-0.91; P=0.0034), respectively. Twenty patients need to be treated with SDD to prevent one gram-negative bloodstream infection and 22 patients to prevent one death.

Mechanical response to methacholine and deep inspiration in supine men

The effects of supine posture on airway responses to inhaled methacholine and deep inspiration (DI) were studied in seven male volunteers. On a control day, subjects were in a seated position during both methacholine inhalation and lung function measurements. On a second occasion, the whole procedure was repeated with the subjects lying supine for the entire duration of the study. On a third occasion, methacholine was inhaled from the seated position and measurements were taken in a supine position. Finally, on a fourth occasion, methacholine was inhaled from the supine position and measurements were taken in the seated position. Going from sitting to supine position, the functional residual capacity decreased by approximately 1 liter in all subjects. When lung function measurements (pulmonary resistance, dynamic elastance, residual volume, and maximal flows) were taken in supine position, the response to methacholine was greater than at control, and this was associated with a greater dyspnea and a faster recovery of dynamic elastance after DI. By contrast, when methacholine was inhaled in supine position but measurements were taken in sitting position, the response to methacholine was similar to control day. These findings document the potential of the decrease in the operational lung volumes in eliciting or sustaining airflow obstruction in nocturnal asthma. It is speculated that the exaggerated response to methacholine in the supine posture may variably contribute to airway smooth muscle adaptation to short length, airway wall edema, and faster airway renarrowing after a large inflation.

Cysteinyl-leukotrienes in the regulation of beta2-adrenoceptor function: an in vitro model of asthma

Background

The response to β₂-adrenoceptor agonists is reduced in asthmatic airways. This desensitization may be in part due to inflammatory mediators and may involve cysteinyl-leukotrienes (cysteinyl-LTs). Cysteinyl-LTs are pivotal inflammatory mediators that play important roles in the pathophysiology of asthma, allergic rhinitis, and other inflammatory conditions. We tested the hypothesis that leukotriene D₄ (LTD₄) and allergen challenge cause β₂-adrenoceptor desensitization through the activation of protein kinase C (PKC).

Methods

The isoproterenol-induced cAMP accumulation was evaluated in human airway smooth muscle cell cultures challenged with exogenous LTD₄ or the PKC activator phorbol-12-myristate-13-acetate with or without pretreatments with the PKC inhibitor GF109203X or the CysLT₁R antagonist montelukast. The relaxant response to salbutamol was studied in passively sensitized human bronchial rings challenged with allergen in physiological salt solution (PSS) alone, or in the presence of either montelukast or GF109203X.

Results

In cell cultures, both LTD₄ and phorbol-12-myristate-13-acetate caused significant reductions of maximal isoproterenol-induced cAMP accumulation, which were fully prevented by montelukast and GF109203X, respectively. More importantly, GF109203X also prevented the attenuating effect of LTD₄ on isoproterenol-induced cAMP accumulation. In bronchial rings, both montelukast and GF109203X prevented the rightward displacement of the concentration-response curves to salbutamol induced by allergen challenge.

Conclusion

LTD₄ induces β₂-adrenoceptor desensitization in human airway smooth muscle cells, which is mediated through the activation of PKC. Allergen exposure of sensitized human bronchi may also cause a β₂-adrenoceptor desensitization through the involvement of the CysLT₁R-PKC pathway.

CCR5 promoter polymorphisms and HIV-1 perinatal transmission in Brazilian children

The frequencies of four CCR5 promoter polymorphisms, and of the Delta32 deletion, have been evaluated in Brazilian HIV-1 positive (HIV+) and HIV-1 negative (HIV-) children, both born from HIV-1 positive mothers and healthy controls (HC), with the aim of investigating whether CCR5 polymorphisms could be associated to vertical transmission of HIV-1. One hundred and six HIV-1 positive children and 70 HIV-1 negative children were enrolled from impoverished areas of Recife (Brazil). We recruited also as healthy controls 104 uninfected children from the same ethnic background, matched for age and known to be not at risk for HIV-1 infection. CCR5 polymorphisms were detected by PCR amplification and direct sequencing. Although no significative divergence was found for CCR5 Delta32, CCR5-59356-C/T and CCR5-59653 C/T polymorphisms, the frequency of CCR5-59353-T/C and CCR5-59402-A/G genotypes differed among HIV+, HIV- and HC children. The presence of the CCR5-59353-TT genotype indicated a trend for increased risk of vertical transmission of HIV-1 infection in Brazilian children, while the presence of the CCR5-59402-AA genotype is suggestive for a protective effect against HIV-1 vertical transmission.

Time-course of diastolic dysfunction in different stages of chronic HCV related liver diseases

AIM

A hyperdynamic circulatory pattern in advanced liver disease is known since a long time. The first studies evaluating cardiac function in cirrhosis were performed in patients with alcoholic liver disease and thus this condition was attributed to the toxic effects of ethanol. A reduced performance of the left ventricle after physical and pharmacological strains along with an altered diastolic function has been demonstrated also in postviral cirrhosis. Many factors are involved in advanced cirrhosis whereas little is known in the earlier stages of disease.

METHODS

To this aim we have investigated patients with different stages of hepatitis C virus (HCV)-related liver disease to detect the time-course of diastolic dysfunction. An impaired relaxation and increased thickness of left ventricular walls along with an altered pattern of transmitral flow can be easily detected by means of echocardiography.

RESULTS

In chronic hepatitis diastolic function is preserved but increased thickness of left ventricle parietal walls can be detected in patients with fibrosis on liver biopsy. The typical pattern of diastolic dysfunction is observed in Child A cirrhotic patients and in Child C ascitic patients but thickness of parietal walls is more relevant in the former group. Chronic aldosterone blockade could exert favourable effects in heart remodeling suggesting a potential role of these drugs in cirrhotic cardiomyopathy.

CONCLUSIONS

The presence of increased thickness of left ventricle parietal walls in chronic hepatitis C in the precirrhotic stage point to a putative role of HCV in this heart structural abnormality that can become a co-factor in the more advanced stages of cirrhosis when portal hypertension and its deleterious effects on systemic hemodynamics, cardiac function and structure become manifest.

A model of allergen-driven human airway contraction: beta2 pathway dysfunction without cytokine involvement

BACKGROUND

In our previous in vitro model, allergen incubation of passively sensitized human airways reduced the response to salbutamol. However, whether cytokines play a role in this model is still unknown.

OBJECTIVE

To investigate interleukin 1beta and tumor necrosis factor a expression in allergen-challenged human airways.

METHODS

Nonasthmatic airways (n = 13) were passively sensitized by overnight atopic serum incubation and then challenged with allergen for 1 hour (n = 9). After repeated washouts, airways were immersed in physiologic salt solution for 6 hours and finally in formaldehyde for immunohistochemical studies. The effect of co-incubation in anti-interleukin 1beta and anti-tumor necrosis factor a specific neutralizing antibodies on salbutamol response was also studied (n = 4).

RESULTS

No differences were found among control, sensitized, and challenged rings in the number of inflammatory cells. The percentage of basement membrane covered by epithelium was similar in the different conditions. There was a higher percentage of degranulating to total mast cells in allergen-challenged rings than in sensitized rings (P < .001). A significant correlation was observed between allergen-induced contraction and mast cell degranulation (r = 0.88; P < .001). The sensitization procedure was validated by paired allergen-induced contractions. No expression of the 2 cytokines was detectable up to 6 hours after allergen challenge, and specific neutralizing antibodies did not attenuate the impaired response to salbutamol in allergen-challenged rings.

CONCLUSION

These data suggest that in our in vitro model of allergic inflammation, beta2 pathway dysfunction can occur without cytokine involvement, thus supporting previous results that suggest a role for leukotrienes.

Correlation of nasal inflammation and nasal airflow with forced expiratory volume in 1 second in patients with perennial allergic rhinitis and asthma

BACKGROUND

Allergic rhinitis and asthma are frequently associated and are characterized by TH2-dependent inflammation. Nasal and bronchial obstruction largely depend on allergic inflammation.

OBJECTIVE

To evaluate the relationships among nasal eosinophil counts, interleukin 4 (IL-4) and interferon-gamma (IFN-gamma) levels, nasal airflow, and forced expiratory volume in 1 second (FEV1) in patients with perennial allergic rhinitis and asthma.

METHODS

Eight men and 7 women (mean +/- SD age, 24.8 +/- 4.7 years) with perennial allergic rhinitis and asthma were evaluated. All 15 patients had a moderate-to-severe grade of nasal obstruction. Total symptom score, rhinomanometry, nasal lavage, nasal scraping, and spirometry were evaluated in all patients. Eosinophils were counted using conventional staining; IL-4 and IFN-gamma levels were measured by immunoassay in fluids recovered from nasal lavage.

RESULTS

Significant positive relationships were demonstrated between eosinophil infiltration and IL-4 levels, nasal airflow and IFN-gamma levels, FEV1 and IFN-gamma levels, and nasal airflow and FEV1 (P < .001 for all). Significant negative relationships were demonstrated between eosinophil infiltration and IFN-gamma levels, IL-4 and IFN-gamma levels, eosinophil infiltration and nasal airflow, IL-4 values and nasal airflow, nasal eosinophil counts and FEV1, and IL-4 values and FEV1 (P < .001 for all).

CONCLUSIONS

There is a close association between TH2 cytokines and eosinophil infiltration in the nose. There is also clear evidence concerning the relationships among eosinophil infiltration, IL-4 and IFN-gamma levels, and nasal airflow. Nasal eosinophil, IL-4, and IFN-gamma levels correlate with FEV1. Finally, nasal airflow is related to FEV1. These findings constitute the first evidence of a relationship between TH2-related nasal inflammation and nasal and bronchial airflow in patients with perennial allergic rhinitis and asthma.

Eosinophils, specific hyperreactivity and occurrence of late phase reaction in allergic rhinitis

BACKGROUND

Eosinophil infiltration may be considered characteristic of nasal allergic inflammation. However, a mild inflammatory infiltrate may be present in asymptomatic subjects exposed to specific allergen.

OBJECTIVE

We investigated the relationship between inflammation, specific hyperreactivity and clinical late phase reactions in allergic subjects using the ASNC model.

METHODS

Sixty allergic subjects (aged from 18 to 47 years) were enrolled among those sensitized to pollens (n=20) and those to house dust mite with (n=20) or without (n=20) known clinical nasal LPR. All subjects were asymptomatic. TNSS and eosinophil number were assessed at baseline, 30 min (early phase) and 6 hours (late phase) after ASNC.

RESULTS

Eosinophil number was higher in LPR+ rhinitics than in other groups, at baseline and during the early and late phase (p<0.001). ATD was lower in LPR+ rhinitics than in other groups (p<0.001). In LPR+ rhinitics, at baseline there was a significant correlation between eosinophils and ATD (r=0.56, p=0.009). After allergen challenge, TNSS was significantly higher in LPR+ rhinitics than in other groups, both during early and late phase (p<0.001 for all comparisons).

CONCLUSIONS

In house dust mite sensitised subjects, LPR occurrence after allergen challenge is associated with higher inflammation and lower ATD at baseline. Therefore, in house dust mite allergy minimal persistent inflammation without symptoms can drive different clinical responses to allergen challenge.

The natural history of allergy: the development of new sensitizations in asthmatic children

Allergy is an important risk factor for asthma in children as most of asthmatic children are sensitized. The aim of the study was to investigate the natural course of sensitizations in a group of children (340) at the onset of asthmatic symptoms. We subdivided children in three groups depending on the age at first visit (3-7-11 years) and followed them for 4 years. All children underwent three visits, each including skin prick test, every two years. In the 3-year age group (n = 133), 59% of children were sensitized at first visit, but the percentage increase to 88% at third visit. When looking only at allergic children at first visit (261), we demonstrated that polysensitization became higher than monosensitization since the age of 11. Analysis of sensitization distribution over the time revealed that house dust mites were prominent from the age of 3 years. Parietaria and grass pollens as well as olive pollen significantly increased, particularly during the 4-year follow-up in the 7-year group. Analysis of sensitization score demonstrated that the age range from 3 to 11 is at high risk to polysensitization. In conclusion, this study provides evidence that sensitization is frequent in asthmatic children, polysensitization represents the natural history of allergy and the type of immune response should appear different for each allergen.

Nasal eosinophils correlate with FEV1 in patients with perennial allergic rhinitis associated to asthma

BACKGROUND

Eosinophil inflammation is present in nasal and bronchial mucosa and a clear link between upper and lower airways exists. Our aim was to evaluate whether nasal inflammation correlates with lung function in patients with perennial allergic rhinitis associated with asthma.

METHODS

Eighty perennial allergic rhinitics with mild asthma, aged from 18 to 46 years, were enrolled. Nasal scraping and spirometry were performed in all subjects.

RESULTS

A close relationship between the nasal eosinophil number and the percentage of predicted FEV1 was demonstrated (r = -0.76; p<0.0001). CONCLUSIONS Nasal cytology may be considered a non-invasive tool to assess airway inflammation in mild asthmatics with associated allergic rhinitis.

Improved bronchodilator effect of deep inhalation after allergen avoidance in asthmatic children

BACKGROUND

In healthy adults and children, deep inhalation (DI) is able to reverse induced bronchoconstriction. This ability is impaired in asthma, but the reasons are still to be elucidated.

OBJECTIVES

This study investigated whether the bronchodilator effect of DI during methacholine-induced bronchoconstriction can be improved by allergen avoidance in asthmatic children, and its relationship with airway inflammation.

METHODS

The effect of DI on methacholine-induced bronchoconstriction was studied at the beginning and the end of a 3-month allergen avoidance period at high altitude in 14 allergic asthmatic children who had severe asthma attacks. Changes in airway caliber were inferred from the respiratory resistance (Rrs) measured by a forced oscillation technique. Results were related to the percentage of eosinophils in induced sputum and compared with those obtained in 9 age-matched nonasthmatic children.

RESULTS

In asthmatic subjects, DI had no significant effect on methacholine-induced increase in Rrs before (P=.62) but significantly reversed it after (P <.01) allergen avoidance. However, the ability of DI to reverse a methacholine-induced increase in Rrs tended to remain less in asthmatic than nonasthmatic children even after allergen avoidance (P=.05). In the asthmatic children, the percentage of eosinophils in induced sputum was decreased at the end of the allergen avoidance period (P <.001), without any significant correlation between sputum eosinophils and airway responsiveness to methacholine or effect of DI.

CONCLUSION

A short period of allergen avoidance may improve the ability of DI to reverse induced bronchoconstriction in some asthmatic children. This effect is associated, yet not correlated, with a reduction in airway inflammation.

Airway function and nasal inflammation in seasonal allergic rhinitis and asthma

BACKGROUND

Allergic rhinitis (AR) and asthma are frequently associated and characterized by a Th2-dependent inflammation. Nasal and bronchial obstruction may be objectively measured.

OBJECTIVE

The aim of this study was to evaluate the relationships among upper and lower airway function and nasal inflammation in subjects with seasonal allergic rhinitis (SAR) and asthma.

METHODS

Twenty out-patients (12 males and eight females, mean age: 23.4+3.6 years) with SAR and asthma were evaluated during the pollen season. All of them showed a moderate-severe grade of nasal obstruction. Total symptom score, rhinomanometry, spirometry, nasal lavage, and nasal scraping were obtained in all subjects. Eosinophils were counted by conventional staining; IL-4 and IFN-gamma were measured by immunoassay on fluids recovered from nasal lavage.

RESULTS

Functional parameters, i.e. nasal airflow and forced expiratory volume in 1 s (FEV(1)), were correlated with nasal eosinophils (R(2)>0.83, P<0.001). Inflammatory parameters, i.e. eosinophils were correlated with immunological parameters, i.e. IL-4 and IFN-gamma levels (R(2)=0.93, P<0.001). Nasal symptoms were correlated with nasal airflow (rho=-0.71, P< or =0.01) and eosinophils (rho=0.72, P<0.01). Nasal airflow was correlated with FEV(1) (r=0.89, P<0.0001).

CONCLUSIONS

This study demonstrates the close connection between Th2 cytokines and eosinophil infiltration in the nose. There is also clear evidence concerning the relationships between eosinophils infiltration and cytokines levels. Nasal eosinophils can be regarded as the most important predictors of upper and lower airway functions. These findings constitute first evidence of a relationship among nasal Th2-related inflammation and nasal and bronchial airflow in patients with SAR and asthma.

Cetirizine reduces cytokines and inflammatory cells in children with perennial allergic rhinitis

Cetirizine has been demonstrated able of reducing nasal inflammatory infiltration in children with allergic rhinitis and cytokine production in in vitro studies. The aim of this double-blind, placebo-controlled, and randomized study was to evaluate cytokine pattern and inflammatory cells in children with perennial allergic rhinitis, before and after treatment with cetirizine or placebo. Twenty children with perennial allergic rhinitis were evaluated, 13 males and 7 females (mean age 13.4 years). Inflammatory cells and cytokines were evaluated by scraping and nasal lavage, before and after 2-weeks administration of cetirizine or placebo. IL4 and IL8 were measured by immunoassay and inflammatory cells were counted by conventional staining. Cetirizine treatment induced a significant decrease of IL4 (p<0.01) and IL8 levels (p=0.01). A significant reduction of the inflammatory cells was detected in actively-treated children, both concerning neutrophils and eosinophils (p<0.01). Moreover, cetirizine significantly reduced nasal obstruction score (p=0.007). This study shows the cetirizine effectiveness in exerting anti-inflammatory activity by modulating cytokine pattern and by reducing inflammatory infiltration in children with perennial allergic rhinitis.

Prevention of MRSA pneumonia by oral vancomycin decontamination: a randomised trial

This study was undertaken to assess whether oropharyngeal vancomycin may control oropharyngeal carriage and lower airway infection due to methicillin-resistant Staphylococcus aureus (MRSA) acquired in the intensive care unit (ICU). Secondary endpoints were the emergence of vancomycin-resistant enterococci, vancomycin-intermediate S. aureus and vancomycin consumption. A total of 84 patients, admitted to a medical/surgical ICU and mechanically ventilated for >72 h, were randomly assigned to control (n=42) or test (n=42) group. Both groups received the protocol of selective decontamination of the digestive tract, including polymyxin E, tobramycin and amphotericin B. Patients in the test group received 0.5 g of a 4% vancomycin gel at 6-h intervals in the oropharynx. Lower airway infections due to MRSA acquired on the ICU were reduced in the test group, as was oropharyngeal carriage. Neither vancomycin-resistant enterococci nor vancomycin-intermediate S. aureus were isolated from either surveillance or diagnostic samples during the study period. The vancomycin costs were lower in the test group. This study demonstrates that oropharyngeal vancomycin, which controls intensive care unit-acquired lower airway infections and secondary carriage due to methicillin-resistant Staphylococcus aureus, is cost-effective and safe in terms of vancomycin-resistant enterococci and vancomycin-intermediate Staphylococcus aureus.

Nasal Obstruction in Patients with Seasonal Allergic Rhinitis: Relationships between Allergic Inflammation and Nasal Airflow

BACKGROUND

Nasal obstruction is a typical symptom of allergic rhinitis. Allergic rhinitis is characterized by a Th2-dependent inflammation. The aim of this study was to evaluate the possible relationships between allergic inflammation, including inflammatory cells and cytokine pattern, and nasal airflow in patients with nasal obstruction due to seasonal allergic rhinitis.

METHODS

Fifty patients (31 males and 19 females, mean age 31.9 +/- 4.8 years) with seasonal allergic rhinitis were evaluated during the pollen season. All of them had moderate to severe nasal obstruction. Total symptom score, rhinomanometry, nasal lavage, and nasal scraping were assessed in all subjects. Inflammatory cells were counted by conventional staining; IL-4, IL-5, IL-8, and IFNgamma were measured by immunoassay on fluids recovered from nasal lavage.

RESULTS

Significant positive relationships were demonstrated between eosinophil infiltration and IL-4 levels (p < 0.0001), eosinophils and IL-5 levels (p < 0.0001), and eosinophils and IL-8 levels (p < 0.0001). Significant negative relationships were demonstrated between eosinophil infiltration and IFNgamma levels (p < 0.0001) and eosinophil infiltration and nasal airflow (p < 0.001).

CONCLUSIONS

This study demonstrates the close connection between Th2 cytokines and eosinophil infiltration. In addition, there is clear evidence concerning the relationship between eosinophil infiltration and nasal airflow. These findings constitute first evidence of the relationship between nasal airflow impairment and Th2-related inflammation in seasonal allergic rhinitis.

Cytokines evaluation in nasal lavage of allergic children after Bacillus clausii administration: a pilot study

Respiratory infections are very frequent in children. Bacillus clausii has been demonstrated to exert some immunomodulatory activities and to be safe. We conducted a study to investigate whether B. clausii administration in allergic children with recurrent respiratory infections might modulate cytokine pattern. Ten children (mean age 4.4 yr) attending the nursery school were enrolled at the end of school year (i.e. in the summer). Bacillus clausii spores (Enterogermina): 2 billion spores per vial) were administered at the dosage schedule of two vials a day for 4 wk. A panel of cytokines, including interleukin (IL)-1, IL-3, IL-4, IL-6, IL-8, IL-10, IL-12, interferon (IFN)-gamma, transforming growth factor (TGF)-beta, and tumor necrosis factor (TNF)-alpha, was measured by immunoassay in the fluid recovered from nasal lavage, performed before and after the treatment. Bacillus clausii treatment induced a significant decrease of IL-4 levels (p < 0.01) and a significant increase of IFN-gamma (p < 0.05), IL-12 (p < 0.001), TGF-beta (p < 0.05), and IL-10 (p < 0.05) levels. Other cytokines were not significantly modified. In conclusion, this study shows that the B. clausii may exert immunomodulating activity by affecting cytokine pattern at nasal level in allergic children with recurrent respiratory infections.

Duration of antiinflammatory and symptomatic effects after suspension of intranasal corticosteroid in persistent allergic rhinitis

BACKGROUND

Allergic rhinitis is characterized by an inflammatory response consequent to allergen exposure. Intranasal corticosteroids represent a first line treatment, but there is no adequate knowledge concerning the duration of symptomatic and antiinflammatory effects after their suspension. Thus, we aimed at investigating this issue.

METHODS

Twelve children with persistent allergic rhinitis were treated with FPANS for 30 days and were followed for 12 days after its suspension. Nasal symptoms, considered as TSS, and inflammatory cells, recovered by nasal scraping, were evaluated.

RESULTS

FPANS significantly reduced TSS (p<0.0001), neutrophils (p<0.001), and eosinophils (p<0.0001) after 4 days of treatment. Symptoms and cellular infiltrate quickly reappeared after suspension (respectively after 3 days for symptoms (p<0.05), after 4 days for neutrophils (p<0.05), and 6 days for eosinophils (p<0.001).

CONCLUSION

These findings suggest that nasal corticosteroid treatment is highly effective in nasal symptoms' relief and inflammation's control, but its suspension induces a rapid reappearance of them.