COVID-19 and the differences in physiological background between children and adults and their clinical consequences.

The SARS-CoV-2 pandemic has indeed been one of the most significant problems facing the world in the last decade. It has affected (directly or indirectly) the entire population and all age groups. Children have accounted for 1.7 % to 2 % of the diagnosed cases of COVID-19. COVID-19 in children is usually associated with a mild course of the disease and a better survival rate than in adults. In this review, we investigate the different mechanisms which underlie this observation. Generally, we can say that the innate immune response of children is strong because they have a trained immunity, allowing the early control of infection at the site of entry. Suppressed adaptive immunity and a dysfunctional innate immune response is seen in adult patients with severe infections but not in children. This may relate to immunosenescence in the elderly. Another proposed factor is the different receptors for SARS-CoV-2 and their differences in expression between these age groups. In infants and toddlers, effective immune response to viral particles can be modulated by the pre-existing non-specific effect of live attenuated vaccines on innate immunity and vitamin D prophylaxis. However, all the proposed mechanisms require verification in larger cohorts of patients. Our knowledge about SARS-CoV-2 is still developing.

Exhaled and Nasal Nitric Oxide - Impact for Allergic Rhinitis.

FeNO measurement is a validated non-invasive technique, which is used for diagnosis and monitoring of asthma. It would be desirable to find a reliable method to monitor allergic rhinitis (AR) via measurement of FeNO, and/or nasal nitric oxide (nNO). The aim of our study was the assessment of the efficacy of FeNO and nNO as markers in AR treatment. FeNO and nNO were measured with the portable NO analyser (NIOX MINO®) in healthy participants and in patients with AR. The patients were examined during the pollen season and out of it. The effect of local corticosteroids and antihistamine therapy was observed in patients with AR during pollen season after three weeks of therapy. There are significant differences between FeNO and nNO in patients with AR compared to healthy controls at all set points of measurements. While FeNO responded well to the treatment with both antihistamines and combined therapy, nNO decreased only after combined therapy with antihistamines and nasal corticosteroids. nNO monitoring alone is not a suitable method to monitor inflammation of the upper airways in AR and its suppression by anti-allergic treatment and should be correlated with other markers as FeNO or symptom scores.

Physiology of nitric oxide in the respiratory system.

Nitric oxide (NO) is an important endogenous neurotransmitter and mediator. It participates in regulation of physiological processes in different organ systems including airways. Therefore, it is important to clarify its role in the regulation of both airway and vascular smooth muscle, neurotransmission and neurotoxicity, mucus transport, lung development and in the. surfactant production. The bioactivity of NO is highly variable and depends on many factors: the presence and activity of NO-producing enzymes, activity of competitive enzymes (e.g. arginase), the amount of substrate for the NO production, the presence of reactive oxygen species and others. All of these can change NO primary physiological role into potentially harmful. The borderline between them is very fragile and in many cases not entirely clear. For this reason, the research focuses on a comprehensive understanding of NO synthesis and its metabolic pathways, genetic polymorphisms of NO synthesizing enzymes and related effects. Research is also motivated by frequent use of exhaled NO monitoring in the clinical manifestations of respiratory diseases. The review focuses on the latest knowledge about the production and function of this mediator and understanding the basic physiological processes in the airways.

Nasal nitric oxide in healthy adults - reference values and affecting factors.

Nitric oxide (NO) is an important endogenous mediator with significant role in the respiratory system. Many endogenous and exogenous factors influence the synthesis of NO and its level is significantly changed during the inflammation. Analysis of nasal nitric oxide (nNO) is not validated so far as the diagnostic method. There is a lack of reference values with possible identification of factors modulating the nNO levels. In healthy adult volunteers (n=141) we studied nasal NO values by NIOX MINO® (Aerocrine, Sweden) according to the recommendations of the ATS & ERS. Gender, age, height, body weight, waist-to-hip ratio, FEV1/FVC, PEF and numbers of leukocytes, eosinophils, basophils and monocytes were studied as potential variables influencing the levels of nNO. The complexity of the results allowed us to create a homogenous group for nasal NO monitoring and these data can be used further as the reference data for given variables. Because of significant correlation between nNO and exhaled NO, our results support the "one airway - one disease" concept. Reference values of nasal NO and emphasis of the individual parameters of tested young healthy population may serve as a starting point in the non-invasive monitoring of the upper airway inflammation.

Effects of surfactant/budesonide therapy on oxidative modifications in the lung in experimental meconium-induced lung injury.

Meconium aspiration syndrome (MAS) is a serious condition, which can be treated with exogenous surfactant and mechanical ventilation. However, meconium-induced inflammation, lung edema and oxidative damage may inactivate delivered surfactant and thereby reduce effectiveness of the therapy. As we presumed that addition of anti-inflammatory agent into the surfactant may alleviate inflammation and enhance efficiency of the therapy, this study was performed to evaluate effects of surfactant therapy enriched with budesonide versus surfactant-only therapy on markers of oxidative stress in experimental model of MAS. Meconium suspension (25 mg/ml, 4 ml/kg) was instilled into the trachea of young rabbits, whereas one group of animals received saline instead of meconium (C group, n = 6). In meconium-instilled animals, respiratory failure developed within 30 min. Then, meconium-instilled animals were divided into 3 groups according to therapy (n = 6 each): with surfactant therapy (M + S group), with surfactant + budesonide therapy (M + S + B), and without therapy (M group). Surfactant therapy consisted of two bronchoalveolar lavages (BAL) with diluted surfactant (Curosurf, 5 mg phospholipids/ml, 10 ml/kg) followed by undiluted surfactant (100 mg phospholipids/kg), which was in M + S + B group enriched with budesonide (Pulmicort, 0.5 mg/ml). Animals were oxygen-ventilated for additional 5 hours. At the end of experiment, blood sample was taken for differential white blood cell (WBC) count. After euthanizing animals, left lung was saline-lavaged and cell differential in BAL was determined. Oxidative damage, i.e. oxidation of lipids (thiobarbituric acid reactive substance (TBARS) and conjugated dienes) and proteins (dityrosine and lysine-lipoperoxidation products) was estimated in lung homogenate and isolated mitochondria. Total antioxidant capacity was evaluated in lung homogenate and plasma. Meconium instillation increased transmigration of neutrophils and production of free radicals compared to controls (P < 0.05). Surfactant therapy, but particularly combined surfactant + budesonide therapy reduced markers of oxidative stress versus untreated animals (P < 0.05). In conclusion, budesonide added into surfactant enhanced effect of therapy on oxidative damage of the lung.

Effects of budesonide on the lung functions, inflammation and apoptosis in a saline-lavage model of acute lung injury.

Diffuse alveolar injury, edema, and inflammation are fundamental signs of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). Whereas the systemic administration of corticosteroids previously led to controversial results, this study evaluated if corticosteroids given intratracheally may improve lung functions and reduce edema formation, migration of cells into the lung and their activation in experimentally-induced ALI. In oxygen-ventilated rabbits, ALI was induced by repetitive saline lung lavage, until PaO2 decreased to < 26.7 kPa in FiO2 1.0. Then, one group of animals was treated with corticosteroid budesonide (Pulmicort susp inh, AstraZeneca; 0.25 mg/kg) given intratracheally by means of inpulsion regime of high-frequency jet ventilation, while another group was non-treated, and both groups were oxygen-ventilated for following 5 hours. Another group of animals served as healthy controls. After sacrifice of animals, left lung was saline-lavaged and protein content was measured and cells in the lavage fluid were determined microscopically. Right lung tissue was used for estimation of edema formation (expressed as wet/dry weight ratio), for histomorphological investigation, immunohistochemical determination of apoptosis of lung cells, and for determination of markers of inflammation and lung injury (IL-1ß, IL-6, IL-8, TNF-α, IFNγ, esRAGE, caspase-3) by ELISA methods. Levels of several cytokines were estimated also in plasma. Repetitive lung lavage worsened gas exchange, induced lung injury, inflammation and lung edema and increased apoptosis of lung epithelial cells. Budesonide reduced lung edema, cell infiltration into the lung and apoptosis of epithelial cells and decreased concentrations of proinflammatory markers in the lung and blood. These changes resulted in improved ventilation. Concluding, curative intratracheal treatment with budesonide alleviated lung injury, inflammation, apoptosis of lung epithelial cells and lung edema and improved lung functions in a lavage model of ALI. These findings suggest a potential of therapy with inhaled budesonide also for patients with ARDS.

N-acetylcysteine effectively diminished meconium-induced oxidative stress in adult rabbits.

Since inflammation and oxidative stress are fundamental in the pathophysiology of neonatal meconium aspiration syndrome (MAS), various anti-inflammatory drugs have been used in experimental and clinical studies on MAS. This pilot study evaluated therapeutic potential of N-acetylcysteine in modulation of meconium-induced inflammation and oxidative lung injury. Oxygen-ventilated adult rabbits were intratracheally given 4 ml/kg of meconium (25 mg/ml) or saline (Sal, n = 6). Thirty minutes later, meconium-instilled animals were treated with intravenous N-acetylcysteine (10 mg/kg, Mec + NAC, n=6) or were non-treated (Mec, n = 6). All animals were oxygen-ventilated for additional 5 hours. Total and differential blood leukocyte counts were determined at baseline, and at 1, 3 and 5 h of the treatment. After sacrificing animals, left lung was saline-lavaged and total and differential cell counts in the bronchoalveolar lavage fluid were determined. Right lung was used for biochemical analyses and for estimation of wet-dry weight ratio. In lung tissue homogenate, thiobarbituric acid-reactive substances (TBARS), dityrosine, lysine-lipid peroxidation (LPO) products, and total antioxidant status (TAS) were detected. In isolated lung mitochondria, TBARS, dityrosine, lysine-LPO products, thiol group content, conjugated dienes, and activity of cytochrome c oxidase were estimated. To evaluate systemic effects of meconium instillation and NAC treatment, TBARS and TAS were determined also in plasma. To evaluate participation of eosinophils in the meconium-induced inflammation, eosinophil cationic protein (ECP) was detected in plasma and lung homogenate. Meconium instillation increased oxidation markers and ECP in the lung and decreased TAS (all P<0.05). NAC treatment reduced ECP and oxidation markers (all P<0.05, except of dityrosine in homogenate and conjugated dienes in mitochondria) and prevented a decrease in TAS (P<0.01) in lung homogenate compared to Mec group. In plasma, NAC decreased TBARS (P<0.001) and ECP, and increased TAS (both P<0.05) compared to Mec group. Concluding, N-acetylcysteine diminished meconium-induced inflammation and oxidative lung injury.

N-acetylcysteine alleviates the meconium-induced acute lung injury.

Meconium aspiration in newborns causes lung inflammation and injury, which may lead to meconium aspiration syndrome (MAS). In this study, the effect of the antioxidant N-acetylcysteine on respiratory and inflammatory parameters were studied in a model of MAS. Oxygen-ventilated rabbits were intratracheally given 4 mL/kg of meconium (25 mg/mL) or saline. Thirty minutes later, meconium-instilled animals were administered N-acetylcysteine (10 mg/kg; i.v.), or were left without treatment. The animals were oxygen-ventilated for additional 5 h. Ventilatory pressures, oxygenation, right-to-left pulmonary shunts, and leukocyte count were measured. At the end of experiment, trachea and lung were excised. The left lung was saline-lavaged and a total and differential count of cells in bronchoalveolar lavage fluid (BAL) was determined. Right lung tissue strips were used for detection of lung edema (expressed as wet/dry weight ratio) and peroxidation (expressed by thiobarbituric acid-reactive substances, TBARS). In lung and tracheal strips, airway reactivity to acetylcholine was measured. In addition, TBARS and total antioxidant status were determined in the plasma. Meconium instillation induced polymorphonuclear-derived inflammation and oxidative stress. N-acetylcysteine improved oxygenation, reduced lung edema, decreased polymorphonuclears in BAL fluid, and diminished peroxidation and meconium-induced airway hyperreactivity compared with untreated animals. In conclusion, N-acetylcysteine effectively improved lung functions in an animal model of MAS.

The influence of L-NAME on iNOS expression and markers of oxidative stress in allergen-induced airway hyperreactivity.

Nitric oxide (NO) effects in airways are influenced by the activity of NO-synthase isoforms and NO metabolism. Inducible NO-synthase (iNOS), which produces large amounts of NO, is active during the inflammatory process. NO quickly reacts, producing reactive oxygen species (ROS). In this study we attempted to detect the expression of iNOS and markers of ROS in the airway hyperreactivity (AHR) condition. The study was performed in guinea pigs, divided into four groups. Two groups were treated with the non-selective inhibitor of NO-synthase L-NAME. The other two groups were used as controls. Exhaled NO was monitored in vivo, AHR was assessed both in vivo and in vitro, and the expression of iNOS in lung homogenate, and oxidative stress markers were measured in the venous blood. L-NAME significantly affected the AHR only in in vitro condition, blocked the expression of iNOS in control but not in sensitized animals, and decreased the level of exhaled NO. The results concerning the oxidative stress markers are equivocal. The study confirmed that NO is involved in the regulation of AHR; the effects being mediated via iNOS and ROS activity.

Thyroid nodules: pathophysiological insight on oncogenesis and novel diagnostic techniques.

Thyroid nodules are a very frequent pathology among common population. Despite the vast majority of them are of benign origin, the incidence of thyroid cancer is currently rather rising. Although there are several risk factors of thyroid cancer and several clinical, ultrasound, biochemical and molecular diagnostic markers, the exact mechanisms of thyroid oncogenesis and the linkage between thyroid nodule ultrasound appearance and its biological character remain unclear. While ionizing radiation is the only one well-known risk factor for thyroid cancer, the significance of some others remains unclear. The aim of our review was to discuss some not completely known pathophysiological mechanisms involved in thyroid oncogenesis as hypothyroidism, mutations of genes regulating cell proliferation, thyroid autoimmunity and pregnancy and to describe pathophysiological background of some ultrasound markers of thyroid cancer (size, echogenicity, vascularization, calcifications and stiffness). Better knowledge in this field is crucial for development of novel diagnostic techniques and therapeutic approaches. For example, the analysis of BRAF, RAS and other mutations in cytological samples may help to distinction between follicular thyroid carcinoma and follicular thyroid adenoma and may significantly decrease the number of unnecessary surgery among patients with thyroid nodules. Alternatively, the different malign cells growth, angiogenesis, destructions of thyroid follicles, reparative changes, growth retardation, fibrosis and increased interstitial fluid pressure implicate the typical ultrasound appearance of papillary thyroid cancer (hypoechogenicity, irregular vascularization, microcalcifications, stiffness) which is essential to catch the suspicious nodules on the basis of their ultrasound appearance among large amount of benign nodules.

Expression of Ki-67, Bcl-2, Survivin and p53 Proteins in Patients with Pulmonary Carcinoma.

Apoptosis is the fundamental process necessary for eliminating damaged or mutated cells. Alterations in the apoptotic pathway appear to be key events in cancer development and progression. Bcl-2 is the key member of the Bcl-2 family of apoptosis regulator proteins with anti-apoptotic effects. Survivin acts as an inhibitor of apoptosis as well and has been implicated in both inhibition of apoptosis and mitosis regulation. p53 is one of the tumor suppressor proteins, prevents tumor formation through cell cycle blocking and eliminates damaged cells via the activation of apoptosis. The Ki-67 protein is a cellular marker for proliferation. To investigate the possible interactions of the aforementioned proteins, we examined their expression in 76 patients with diagnosed lung cancer using immunohistochemical visualisation. Ki-67 protein was expressed in the cancer cells of all patients with small cell lung cancer (SCLC). We found a negative correlation between survivin and p53 expression. A decreased intensity of survivin expression and fewer cells positive for survivin (66.7%) in SCLC in comparison with other lung cancer types (98.0%) was detected. Reversely, expression of Bcl-2 was found in more than 90% of cases with SCLC. We hypothesize that high expression and intensity of Bcl-2 protein could be a factor behind a bad prognosis in SCLC.

L-arginine supplementation and experimental airway hyperreactivity.

The interest in L-arginine metabolism was triggered primarily by the discovery of nitric oxide (NO) synthesis in mammals and its remarkable biological roles. The real role of L-arginine in the airway hyperreactivity (AHR) has not been established yet. Therefore, we studied whether supplementation of L-arginine can influence the experimental AHR evoked by two different triggers - allergen and exogenous irritant (toluene vapours). Male TRIK strain guinea pigs were used in the study. We used two patterns of pretreatment with L-arginine in vivo, short- and long-term, in a dose of 300 mg/kg administered i.p., after which we studied reactivity of airway smooth muscles in vitro. Pretreatment with L-arginine for 3 days decreased the airway smooth muscle reactivity induced by toluene vapour, whereas pretreatment for 17 days was without any additional effect on smooth muscle reactivity. The short-term pretreatment in ovalbumin-induced hyperreactivity caused an increase in airway smooth muscle reactivity to lower concentrations of both bronchoconstrictors. On the other side, this pretreatment significantly decreased smooth muscle reactivity to high concentrations of both bronchoconstrictors. Supplementation of L-arginine resulted in a modification of the airway smooth muscle response. The effect of supplementation was different depending on the AHR trigger, airway region and pretreatment duration. The results also underscore the importance of an optimal L-arginine level for the control of bronchial tone.

[Prognostic significance of morphology in multiple myeloma]. / Prognostický význam morfologického hodnocení u mnohocetného myelomu.

BACKGROUNDS: Multiple myeloma is the second most common hematological disease caused by clonal proliferation of B cells. Evaluation of number of plasmocytes in the bone marrow is still one of the basic diagnostic criteria. The aim of this study was to verify if this evaluation has prognostic value even in the era of new drugs. MATERIAL AND METHODS: Two groups of MM patients were enrolled in this study. The group T - 45 newly diagnosed MM patients who underwent treatment with thalidomide. Group B - 86 patients in first relapse of MM without autologous transplantation of bone marrow that were treated with thalidomide and bortezomib in various combinations. Percentage of subtypes of plasmocytes in the bone marrow was evaluated based on progressive analysis of nucleus, chromatin and nucleo-cellular ratio (N/C). RESULTS: Mature plasma cells were found in 53.3% (group T) and 53.5% (group B) of patients; proplasmocytes I were found in 22.2% (group T) and 24.4% (group B) of patients; proplasmocytes II were found in 22.2% (group T) and 22.1% (group B) of patients and plasmablasts in 1% (group T) and 0% (group B). Patients who reached treatment response after first treatment had statistically significant number of proplasmocytes II when compared to group without treatment response (median 37% vs. 11%, p = 0.033). Group B patients with mature plasmocytes below 10% had significantly shorter overall survival than other patients when comparison of quartiles was performed. Group B patients with higher infiltration of proplasmocytes I than median of 15% had lower overall survival (median 50.3 months vs. 74.9 months, p = 0,024); the same was true for evaluation of proplasmocytes II (median OS 41.3 months vs. 74.9 months, p = 0,011). CONCLUSION: Numerical evaluations of plasma cells in the bone marrow remain basic diagnostic criteria of MM even in the era of new genomics analyses. More precise morphological evaluation of 8 subtypes of plasma cells brings important prognostic information that is necessary for new protocols for immunomodulatory drugs and proteasome inhibitors.

Prognostic significance of morphological assessment of plasma cells in multiple myeloma.

Multiple myeloma (MM) is a hematological malignancy caused by clonal proliferation of malignant plasma cells (PC). The aim of the work is to determine prognostic significance of morphological subtypes of PC in relation to overall treatment response, long-term survival and other conventional prognostic parameters. One hundred and thirty-nine newly diagnosed MM patients who underwent autologous transplantation in clinical trials conducted in one center were included. Percentual representation of subtypes of plasma cells in bone marrow was measured based on progressive analysis of nucleolus, nuclear chromatin and ratio of nuclei to the volume of cytoplasm (N/C ratio) creating 8 subtypes P000-P111 and four subclassifications of cells. Mature plasma cells (P000, P001) were found in 42.4% of patients; proplasmocytes I (P010, P011, P100) in 38.1% of patients, and proplasmocytes II (P101, P110) in 19.4% of patients. Patients who reached treatment response after autologous transplantation had statistically significant lower frequency of mature plasma cells than patients with no treatment response (median 24.0% vs. 36.0 %; p=0.032). Patients with mature plasma cells of subtype P000 an patients with value P000 ≥ 37% (median 46.8 months vs. 77.8 months; p = 0.020). Patients with proplasmocytes II subtype P110 rings valuable prognostic information and correlation with other prognostic factors as well as total treatment response and survival in MM patients who underwent autologous transplantation.

Low prevalence of clinically high-risk women and pathological thyroid ultrasound among pregnant women positive in universal screening for thyroid disorders.

BACKGROUND: It is controversial whether screening program for thyroid disorders in pregnancy should be universal or targeted case-finding. To evaluate the relationship between history, laboratory parameters and thyroid ultrasound (TUS) in pregnant women positive in universal screening. SUBJECTS AND METHODS: The screening included investigation of serum TSH (thyroid stimulating hormone) and TPOAb (antithyroperoxidase antibodies) in 5,520 unselected pregnant women in the 9-11th gestational week. In 822 the screening was positive: abnormal TSH (> 3.67 or < 0.06 mIU/l) and/or positive TPOAb (> 143 kIU/l). 200 consecutive women with positive screening were included it the study. RESULTS: 41 women (21%) had transient gestational hyperthyroidism (TGH) and 159 (79%) had a thyroid pathology: 10 (5%) overt hypothyroidism; 76 (38%) subclinical hypothyroidism, 7 (3.5%) overt hyperthyroidism and 66 (33%) euthyroid TPOAb positivity. After exclusion of TGH, only 74/159 (47%) women were classified as high-risk for thyroid disease according to their history. There were no significant clinical and laboratory differences between the high- vs. low-risk women, except for higher proportion of FT4<75th percentile (P=0.008) and larger thyroid volume in the high-risk group (P=0.04). Finally, only 66/126 (52%) of TPOAb-positive pregnant women had autoimmune pattern in TUS in comparison with 41/49 (84%) TPOAb-positive non-pregnant control women of comparable age (P<0.001). CONCLUSIONS: Less than half of the positively screened pregnant women can be classified as high-risk and almost half of them had not autoimmune pattern in TUS. High- and low-risk pregnant women have similar clinical and laboratory characteristics.

[Airway hyperreactivity]. / Hyperreaktivita dýchacích ciest.

The airway hyperreactivity (AHR) is a symptom occurring in various diseases of the respiratory system. It is defined as an abnormal bronchoconstriction response to a different spectrum of biological, chemical and pharmacological stimuli. Pathogenesis of airway hyperreactivity is not well understood. The available literature data shows that in the AHR pathogenesis is important not only genetic predisposition or influence of combination environmental and genetic factors, but also the presence and activity of various inflammatory mediators and other endogenous factors (growth factors, nuclear transcription factors). In this process is also important role of neural regulation and release of pro-inflammatory neurotransmitters. Our aim was to provide a comprehensive overview of knowledge about the symptoms--from the risk factors and pathogenesis through the clinical importance to the need for better understanding new options in therapeutic interventions.

Arginase in the airways hyperreactivity.

BACKGROUND: The interest of arginase action is increasing because limitation of L-arginine bioavailability by arginase for NO synthesis via constitutive NOS can contribute to airway hyperreactivity. OBJECTIVES: We investigated the effect of intervention in the arginase activity in guinea pig model of experimental ovalbumin-induced airway hyperreactivity. METHODS: We analysed the response of tracheal and lung tissue smooth muscle strips to histamine or acetylcholine after in vitro administration of arginase in a dose of 75 UI or after administration of the non-selective inhibitor of arginase N(omega)-hydroxy-L-arginine (NOHA) in a dose of 5 and 10 micromol. We used as well as the incubation of strips with the precursor of NO synthesis L-arginine in a dose of 10(-4) mol/l together with NOHA. RESULTS: We did not find any significant differences in the reactivity of tracheal and lung tissue smooth muscle if we applied arginase in a dose of 75 UI in vitro. NOHA in a dose of 5 a 10 micromol induced the decrease of tracheal and lung tissue smooth muscle reactivity overall. The decrease of the contraction amplitude was dose-dependent. The supplementation of NO synthesis precursor L-arginine in a dose of 10(-4) mol/l together with NOHA intensified the decrease of the airways reactivity induced by an arginase inhibition. CONCLUSION: The results suggest that arginase is involved in the control of airways bronchomotoric tone and therefore modulation of arginase activity could be a useful tool for airway smooth muscle tone control in clinical conditions (Fig. 7, Ref. 33). Full Text (Free, PDF) www.bmj.sk.

The relationship between thyroid function, serum monokine induced by interferon gamma and soluble interleukin-2 receptor in thyroid autoimmune diseases.

Interactions between cytokines play an important role in the development of thyroid autoimmunity. Using enzyme-linked immunosorbent assay we investigated serum concentrations of soluble interleukin-2 receptor (sIL-2R), interferon-gamma, tumour necrosis factor (TNF)-alpha, interleukin (IL)-10, CD30, monokine induced by interferon-gamma (MIG), cytotoxic T lymphocyte antigen-4 and markers of apoptosis decoy receptor 3 and Bcl-2 in 28 patients with hyperthyroid Graves' disease (GD), 24 patients with untreated Hashimoto's thyroiditis (HT) and 15 healthy controls. TNF-alpha, IL-10 and sIL-2R were higher in GD compared with HT and controls (TNF-alpha: 8.79 in GD versus 2.54 pg/ml in HT, P = 0.01; IL-10: 10.00 versus 3.10 versus 3.10 pg/ml, P(1) < 0.001, P(2) = 0.005; sIL-2R: 1.26 versus 0.64 versus 0.46 ng/ml, P < 0.001). MIG and CD30 were higher in HT compared with controls (649.22 +/- 262.55 versus 312.95 +/- 143.35 pg/ml, P = 0.037, 6.57 +/- 2.35 versus 3.03 +/- 1.04 U/ml, P = 0.036 respectively). In GD sIL-2R decreased when the euthyroid state was achieved (1.31 +/- 0.64 versus 0.260 +/- 0.11, n = 12, P < 0.001). sIL-2R correlated positively with free thyroxine (FT4) (R = 0.521, P = 0.000) and negatively with thyroid stimulating hormone (TSH) (R = -0.472, P = 0.00132). MIG correlated negatively with FT4 (R = -0.573, P = 0.00234) and positively with TSH (R = 0.462, P = 0.0179). The results suggest that serum concentrations of sIL-2R and MIG are related to thyroid function rather than to activation of autoimmunity.

Exhaled nitric oxide - circadian variations in healthy subjects.

OBJECTIVE: Exhaled nitric oxide (eNO) has been suggested as a marker of airway inflammatory diseases. The level of eNO is influenced by many various factor including age, sex, menstrual cycle, exercise, food, drugs, etc. The aim of our study was to investigate a potential influence of circadian variation on eNO level in healthy subjects. METHODS: Measurements were performed in 44 women and 10 men, non-smokers, without respiratory tract infection in last 2 weeks. The eNO was detected at 4-hour intervals from 6 a.m. to 10 p.m. using an NIOX analyzer. We followed the ATS/ERS guidelines for eNO measurement and analysis. RESULTS: Peak of eNO levels were observed at 10 a.m. (11.1 +/- 7.2 ppb), the lowest value was detected at 10 p.m. (10.0 +/- 5.8 ppb). The difference was statistically significant (paired t-test, P<0.001). CONCLUSIONS: The daily variations in eNO, with the peak in the morning hours, could be of importance in clinical practice regarding the choice of optimal time for monitoring eNO in patients with respiratory disease.

Bidirectional link between upper and lower airways in patients with allergic rhinitis.

OBJECTIVE: Exhaled nitric oxide has been proposed as a noninvasive marker of eosinophilic airway inflammation in lower airways. The aim of the study was to investigate the impact of atopy, pollen exposure, and pharmacological treatment on NO production in lower airways of patients with allergic rhinitis. SUBJECTS AND METHODS: Measurements of exhaled NO were performed in 79 non-asthmatic subjects with seasonal allergic rhinitis outside and in pollen season, before and after pharmacological treatment, and in 54 healthy controls. RESULTS: Patients with allergic rhinitis had significantly higher levels of exhaled NO (18.3 +/-11.0 ppb) than healthy controls (13.0 +/-7.2 ppb) measured outside the pollen season (P=;0.0024). Increased exhaled NO levels were also found in patients with allergic rhinitis in the pollen season (27.0 +/-20.0 ppb) compared with the levels outside pollen season (P=0.0001), before pharmacological treatment. In rhinitic patients treated by nasal corticosteroids and antihistamines in the pollen season, the levels of exhaled NO were significantly lower (17.0 +/-16.4 ppb; P=0.045) than those before treatment. No difference was found in NO levels in rhinitic patients outside and in pollen season after pharmacological treatment. CONCLUSIONS: This study has shown the presence of eosinophilic airway inflammation in the lower airways in allergic rhinitis patients. A significant increase of exhaled NO after pollen exposure in rhinitic patients underlies the impact of inflammation on the upper respiratory tract. A bidirectional link between upper and lower airways is confirmed by a decrease in exhaled NO in the pollen season, almost to the starting levels, after application of topic corticosteroids and antihistamines.