Biomedical subjects

Ildikó Horváth

Publications and source records attributed to Ildikó Horváth.

6 recordsLinked to original sources

PubMed2005

[Bronchiolitis obliterans syndrome in lung transplant recipients].

Bronchiolitis obliterans syndrome in lung transplant recipients. The leading cause of late graft loss after lung transplantation is bronchiolitis obliterans syndrome. The process is a manifestation of chronic rejection, and is characterized by an excessive fibroproliferation in the small airways, leading progressively to luminal obliteration and graft injury. Both alloantigen-dependent (acute rejection, histocompatibility) and alloantigen-independent (ischaemia-reperfusion injury, cytomegalovirus infection, gastroesophageal reflux disease) risk factors may contribute to the development of the disease. Early in the process, damage to the airway epithelium occurs, which then triggers a massive influx of alloreactive T-cells into the graft tissue. Activated T-cells release a wide range of cytokines and growth factors, which in turn are capable of stimulating cellular proliferation and matrix protein synthesis in fibroblasts as well as in airway smooth muscle cells. Clinically, a decline in lung functions together with nonspecific symptoms can usually be observed in these patients, while later in the disease course recurrent respiratory tract infections are more common. Up till now, no effective therapy is available for bronchiolitis obliterans syndrome, however, certain immunosuppressive regimens may slow down the progression of the disease.

Animals↗

PubMed2003

[Exhaled breath condensate and its analysis--a new method in pulmonology].

In the middle of the nineties a new, non-invasive method for investigation of the lung aroused the interest of many researchers: the exhaled breath condensate. It shows the extent of the interest that in the last five years more than 80 original articles have been published in this theme. Many substances are found in the expired breath which are detectable in the liquid that we obtain by cooling (= condensing) the exhaled breath. The advantages of this method are that it is non-invasive, convenient, it could be performed with mechanically ventilated patients as well as with children. The most studied substance is the hydrogen-peroxide, which is the marker of oxidative stress, and its level in condensate is elevated in numerous inflammatory diseases. 8-isoprostane was also studied a lot, which is another marker of oxidative stress. Numerous substances could be even measured in condensate, so the decay-product of nitric-oxide (nitrite, nitrate, nitrotyrosine), further nitrosothiol, adenosine, ammonia, different ions, leukotrienes, cytokines; recently even other feature of condensate is examined, such as its pH. The different mediators could help us to know better the diseases, support the diagnosis, follow the treatment or the disease. In this study the authors attempt to present the most important knowledge till now.

Asthma↗

PubMed2002

Comparison of nasal and oral inhalation during exhaled breath condensate collection.

Analysis of exhaled breath condensate is a method for noninvasive assessment of the lung. Condensate can be collected with a nose clip (subjects inhale and exhale via the mouth) or without it (subjects inhale via the nose and exhale via the mouth), but the mode of inhalation may influence condensate volume and mediator levels. We compared condensate volume and adenosine, ammonia, and thromboxane B2 levels in young healthy volunteers (n = 25) in samples collected for 10 minutes from subjects with or without a nose clip. Patients with allergic rhinitis (n = 8) were also studied to assess the effect of upper airway inflammation on mediator levels. Adenosine, ammonia, and thromboxane B2 levels were determined by HPLC, spectrophotometry, and radioimmunoassay, respectively. Volume of condensate was significantly higher without nose clip than that with nose clip (mean +/- SD, 2321 +/- 736 microl and 1746 +/- 400 microl, respectively; p = 0.0001). We found no significant difference in any mediator levels between these two collection modes in healthy volunteers, but adenosine showed a tendency to differ between oral and nasal inhalation in patients with allergic rhinitis. Our data indicate that whereas a greater volume of condensate can be obtained when subjects inhale through their noses, the mode of inhalation does not influence mediator levels in young healthy volunteers, but may affect these levels in patients with allergic rhinitis.

Adenosine↗

PubMed2002

Plasma adenosine concentration increases during exercise: a possible contributing factor in exercise-induced bronchoconstriction in asthma.

We investigated whether the level of plasma adenosine (ADO) changed during exercise and whether this could be related to exercise-induced bronchoconstriction. Baseline levels of ADO did not differ, but exercise resulted in higher ADO in patients with asthma than in healthy subjects (86 +/- 35 vs 59 +/- 16 nmol/L; P <.001). In patients with asthma, the increase in ADO was related to decreases in FEV(1) (r (2) = 0.475; P <.05) and SaO(2) (r (2) = 0.693; P <.05). These data suggest that adenosine might be involved in the development of exercise-induced bronchoconstriction.

Adenosine↗

PubMedDate not supplied

The influence of gastroesophageal reflux disease and its treatment on asthmatic cough.

Gastroesophageal reflux is known to cause chronic cough and is also implicated in worsening of asthma. We conducted a prospective study to examine the clinical significance of gastroesophageal reflux disease (GERD) in asthmatic patients with chronic cough to analyze the temporal relationship between reflux events and coughing and to assess the effect of esomeprazole treatment on respiratory symptoms and lung function in these patients. Asthmatic patients (126) with chronic dry cough were studied. Diagnosis of GERD was based on typical symptoms and the effectiveness of therapeutic test or on pH monitoring. Patients without GERD (negative pH results) consisted of the control group. The results of pH monitoring showed that 64% of cough episodes were related to acid reflux and in 91% of reflux events preceded coughing. Esomeprazole treatment (40 mg/day for 3 months) not only diminished GERD symptoms but also improved asthma outcome Baseline FEV(1) and PEF values increased significantly together with a decrease in symptom scores and the use of rescue medication. In most patients included in the extended part of the study for another 3 months, the dose of inhaled steroids could be reduced with sustained GERD therapy. Our data showing that reflux events preceded coughing in most cases and that treatment of GERD resulted in an improvement in different outcome measures of asthma suggest that GERD worsens asthma, and its treatment is of clinical importance to effectively manage these patients.

Adult↗

PubMedDate not supplied

Exhaled nitric oxide and hydrogen peroxide concentrations in asthmatic smokers.

BACKGROUND: Cigarette smoking is associated with decreased nitric oxide (NO) production and increased oxidative stress in the airways. Exhaled NO levels are not higher in asthmatic smokers than in healthy non-smokers, and the value of exhaled NO for diagnosing asthma in smokers has been questioned. OBJECTIVES: To compare exhaled NO concentrations between healthy and steroid-naive and steroid-treated asthmatic smokers and non-smokers. To also assess the acute effect of cigarette smoking on exhaled NO and hydrogen peroxide (H(2)O(2)) levels in asthmatic smokers. METHODS: Exhaled NO was measured by chemiluminescence and exhaled H(2)O(2) spectrophotometrically. In 7 steroid-naive asthmatic smokers exhaled NO and H(2)O(2) was measured both before and 15 min after smoking one cigarette. Data are given as median (range). RESULTS: Exhaled NO level was significantly higher in steroid-naive asthmatic smokers than in healthy smokers [7.7 (3.4-32.5) ppb vs. 3.2 (2.0-7.2) ppb, p < 0.001]. Exhaled NO values were lower in smokers than in non-smokers both in healthy subjects and in steroid-naive asthmatic patients. Steroid-treated asthmatic smokers had a tendency for lower exhaled NO values [5.4 (1.7-12.0) ppb] compared to steroid-naive asthmatic smokers. Cigarette smoking caused an acute increase in exhaled H(2)O(2) concentrations together with a decrease in exhaled NO concentration. CONCLUSIONS: Our data suggest that an elevation in exhaled NO concentration is associated with asthma in smokers. This difference may be useful for diagnosing the disease in smokers, but its clinical value needs further evaluation. Acute increase in exhaled H(2)O(2) concentrations suggests that smoking increases the oxidative stress in the asthmatic airways.

Adult↗