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Biomedical subjects

H M Jansen

Publications and source records attributed to H M Jansen.

At least 19 recordsLinked to original sources

Adding salmeterol to an inhaled corticosteroid: long term effects on bronchial inflammation in asthma.

BACKGROUND: Addition of the long acting beta2 agonist salmeterol to inhaled corticosteroids leads to better symptomatic asthma control than increasing the dose of inhaled corticosteroids. However, little is known about the long term effects of adding salmeterol on the asthmatic inflammatory process, control of which is considered important for the long term outcome of asthma. METHODS: After a 4 week fluticasone run-in period, 54 patients with allergic asthma were randomised to receive twice daily treatment with fluticasone 250 microg with or without salmeterol 50 microg for 1 year in a double blind, parallel group design (total daily dose of fluticasone 500 microg in both treatment groups). Primary outcomes were sputum eosinophil numbers and eosinophil cationic protein concentrations. Secondary outcomes were neutrophil associated sputum parameters and a respiratory membrane permeability marker. The effects on allergen induced changes were determined before and at the end of the treatment period. RESULTS: Adding salmeterol to fluticasone resulted in improved peak expiratory flow, symptom scores, rescue medication usage, and bronchial hyperresponsiveness (p < 0.05 for all). There was no sustained effect on sputum cell differential counts and cytokine concentrations during the treatment period or on changes induced by allergen challenge at the end of treatment (p > 0.05). However, adding salmeterol significantly reduced sputum ratios of alpha2-macroglobulin and albumin during the treatment period (p = 0.001). CONCLUSIONS: The addition of salmeterol to fluticasone produces no sustained effect on allergen induced cellular bronchial inflammation but leads to a significant improvement in size selectivity of plasma protein permeation across the respiratory membrane. This may contribute to the improved clinical outcome seen in patients with allergic asthma when a long acting beta2 agonist is combined with inhaled corticosteroids.

Administration, Inhalation↗

Toll-like receptor mRNA levels in alveolar macrophages after inhalation of endotoxin.

Toll-like receptors (TLRs) are pattern-recognition receptors that have been implicated in the initiation of innate immune responses upon the first encounter with invading pathogens. The airways are frequently exposed to various types of lipopolysaccharide (LPS) from the environment or from pathogens. The current study was designed to determine the effect of LPS on TLR gene expression in human alveolar macrophages in vivo. In total, 16 healthy subjects were enrolled in a single-blinded, placebo-controlled study. Subjects inhaled 100 microg LPS or normal saline (n = 8 per group). Measurements were performed in alveolar macrophages purified from bronchoalveolar lavage fluid obtained 6 h post-challenge. Inhalation of LPS by healthy human volunteers resulted in enhanced alveolar macrophage expression of mRNAs encoding TLRs 1, 2, 7, 8 and CD14, and reduced expression of mRNAs encoding TLR4 and lymphocyte antigen 96. In conclusion, lipopolysaccharide differentially influences the toll-like receptor mRNA expression profile in human alveolar macrophages in vivo.

Administration, Inhalation↗

Value of intensive diagnostic microbiological investigation in low- and high-risk patients with community-acquired pneumonia.

In a prospective study to evaluate the diagnostic yield of different microbiological tests in hospitalised patients with community-acquired pneumonia, material for microbiological investigation was obtained from 262 patients. Clinical samples consisted of the following: sputum for Gram staining, culture, and detection of pneumococcal antigen; blood for culture and serological tests; urine for detection of Legionella pneumophila serogroup 1 antigen and pneumococcal antigen; and specimens obtained by fiberoptic bronchoscopy. A pathogen was identified in 158 (60%) patients, with Streptococcus pneumoniae (n=97) being the most common causative agent of community-acquired pneumonia. In 82% of the 44 patients with an adequate sputum specimen, a positive Gram stain was confirmed by positive sputum culture. S. pneumoniae infections were detected principally when adequate sputum specimens were examined by Gram stain and culture and when adequate and inadequate sputum specimens were tested for the presence of pneumococcal antigen (n=58; 60%). The urinary pneumococcal antigen test was the most valuable single test for detection of S. pneumoniae infections (n=52; 54%) when sputum pneumococcal antigen determination was not performed. Fiberoptic bronchoscopy was of additive diagnostic value in 49% of the patients who did not expectorate sputum and in 52% of those in whom treatment failed. Investigation of sputum by a combination of Gram stain, culture, and detection of pneumococcal antigen was the most useful means of establishing an aetiological diagnosis of community-acquired pneumonia, followed by testing of urine for pneumococcal antigen. Fiberoptic bronchoscopy may be of additional value when treatment failure occurs.

Community-Acquired Infections↗

Comparison between pathogen directed antibiotic treatment and empirical broad spectrum antibiotic treatment in patients with community acquired pneumonia: a prospective randomised study.

BACKGROUND: There is much controversy about the ideal approach to the management of community acquired pneumonia (CAP). Recommendations differ from a pathogen directed approach to an empirical strategy with broad spectrum antibiotics. METHODS: In a prospective randomised open study performed between 1998 and 2000, a pathogen directed treatment (PDT) approach was compared with an empirical broad spectrum antibiotic treatment (EAT) strategy according to the ATS guidelines of 1993 in 262 hospitalised patients with CAP. Clinical efficacy was primarily determined by the length of hospital stay (LOS). Secondary outcome parameters for clinical efficacy were assessment of therapeutic failure on antibiotics, 30 day mortality, duration of antibiotic treatment, resolution of fever, side effects, and quality of life. RESULTS: Three hundred and three patients were enrolled in the study; 41 were excluded, leaving 262 with results available for analysis. No significant differences were found between the two treatment groups in LOS, 30 day mortality, clinical failure, or resolution of fever. Side effects, although they did not have a significant influence on the outcome parameters, occurred more frequently in patients in the EAT group than in those in the PDT group (60% v 17%, 95% CI -0.5 to -0.3; p<0.001). CONCLUSIONS: An EAT strategy with broad spectrum antibiotics for the management of hospitalised patients with CAP has comparable clinical efficacy to a PDT approach.

Adult↗

Abnormal radiological findings and a decreased carbon monoxide transfer factor can persist long after the acute phase of Legionella pneumophila pneumonia.

Pulmonary abnormalities may persist long after the acute phase of legionnaires disease (LD). In a cohort of 122 survivors of an outbreak of LD, 57% were still experiencing an increased number of symptoms associated with dyspnea at a mean of 16 months after recovery from acute-phase LD. For 86 of these patients, additional evaluation involving high-resolution computed tomography (HRCT) of the lung revealed pulmonary abnormalities in 21 (24%); abnormal HRCT findings generally presented as discrete and multiple radiodensities. Residual pulmonary abnormalities were associated with a mean reduction of 20% in the gas transport capacity of the lung. This latter sign could not be used to explain the increased symptoms of dyspnea reported by patients. Receipt of mechanical ventilation during the acute phase of LD, delayed initiation of adequate antibiotic therapy, and chronic obstructive pulmonary disease were identified as risk factors for the persistence of lung abnormalities.

Aged↗

Prospective evaluation of pneumonia severity index in hospitalised patients with community-acquired pneumonia.

The aim of the present study was to investigate whether the pneumonia severity index (PSI) could adequately predict the severity of community-acquired pneumonia (CAP) and could be used as a severity of illness classification system. Furthermore, reasons that may influence the decision to admit low risk patients were analysed. In a prospective study 260 patients with CAP were included. Stratification in five risk classes according to the PSI was compared with parameters that are closely related to severity of CAR A significant difference in severity parameters, such as length of stay (P < 0.001) and simplified acute physiologic score and acute physiologic and chronic health evaluation II score (P < 0.001) was found between the five risk classes. Furthermore, a positive British Thoracic Society (BTS) rule and modified BTS rule score was significantly more prevalent in the higher risk classes (P < 0.001). The patient population had an average 30-day mortality of 10% and a mean Intensive Care Unit (ICU) admission rate of 8%. The mortality rate and ICU admission rate significantly differed between the five risk classes (P < 0.001), in which the highest ICU admission rate (40.9%) and the highest mortality percentage (40.9%) were both found in risk class V. Several clinical factors (n = 64), such as an exacerbation of chronic obstructive pulmonary disease in 17 patients and clinical appearance of being ill in 16 patients, lack of improvement on outpatient antibiotic therapy (n = 15) and social circumstances (n = 3) were reasons that influenced the decision to hospitalise low risk patients (n = 82). The results show that the PSI adequately predicted the severity of CAP and can be used as a severity of illness classification in CAP. Clinical and social factors other than those mentioned in the PSI have to be considered when making the decision to hospitalise patients with CAP.

APACHE↗

Serum surfactant protein D is elevated in allergic patients.

BACKGROUND: There is evidence that surfactant protein (SP)-D is important in the innate, as well as in the adaptive pulmonary immune response. Serum concentrations of SP-D have been proposed as parameter of the integrity of the blood-airspace barrier in interstitial lung diseases. We hypothesized that serum SP-D concentrations are affected in allergic patients and correlate with changes in allergic airway inflammation. OBJECTIVE: To determine levels of serum SP-D in allergic patients compared with non-allergic controls. Furthermore, to investigate associations between serum SP-D concentrations on the one hand and changes in commonly used markers of bronchial inflammation in allergic airways disease on the other hand. MATERIALS AND METHODS: Fifty allergic patients were studied and bronchial allergen challenge was used as a model to increase bronchial allergic inflammation in these patients. Serum SP-D concentrations, inflammatory parameters in induced sputum and bronchial hyper-responsiveness (BHR) were determined before and after allergen challenge. Twenty-five non-allergic volunteers served as controls. RESULTS: Baseline serum SP-D was significantly higher in allergic patients as compared with controls (mean serum SP-D concentration (95% confidence interval): 62.7 (55.5, 70.0) in allergic patients vs. 49.5 (36.7, 62.3) ng/mL in non-allergic controls, P=0.006). In addition, baseline serum SP-D appeared to be an independent predictor for the magnitude of the late asthmatic response after allergen challenge. Furthermore, serum SP-D was predictive for the sputum eosinophil cationic protein concentration after allergen challenge. CONCLUSION: We propose that serum SP-D concentrations are associated with allergic bronchial inflammation and may give additional information, beside BHR and sputum eosinophils, about the degree of bronchial inflammation in allergic patients.

Adult↗

A comparison of salmeterol and formoterol in attenuating airway responses to short-acting beta2-agonists.

In vitro data suggest that salmeterol, contrary to formoterol, can partly antagonise the effect of short-acting beta(2)-agonist rescue medication. To explore whether this occurs in vivo, we compared the effects of increasing doses (200-3200 microg) of fenoterol on the recovery of methacholine induced bronchoconstriction as well as PD(20) methacholine in 23 asthmatic patients, during two-week treatment periods with placebo, and standard doses of salmeterol or formoterol in a double blind, double-dummy, crossover study. Salmeterol showed a slightly higher propensity for the development of bronchodilator tolerance. The recovery of methacholine induced bronchoconstriction was more complete during regular use of formoterol relative to salmeterol. During regular use of both long-acting beta(2)-agonists the bronchoprotective efficacy of fenoterol was attenuated, but this was more pronounced during salmeterol than during formoterol. The mean maximum increase in PD(20) metacholine after the highest dose of fenoterol was 3.97 DD during placebo, 2.47 DD during formoterol (p<0.001) and 1.81 DD during salmeterol treatment (p<0.001). We conclude that in asthmatic patients the efficacy of short-acting beta(2)-adrenoceptor agonists can be significantly attenuated during regular use of long-acting beta(2)-agonists. In this respect, differences were observed between salmeterol and formoterol that may represent the expression of partial antagonism by salmeterol.

Adrenergic beta-Agonists↗

Similar levels of nitric oxide in exhaled air in non-asthmatic rhinitis and asthma after bronchial allergen challenge.

BACKGROUND: Nitric oxide in exhaled air (eNO) is elevated in allergic asthma compared with healthy subjects and has been proposed as a marker of bronchial inflammation. However, eNO is elevated to a lesser extent in allergic non-asthmatic rhinitis as well. Considering the distinctive clinical appearances of both allergic diseases, differences in eNO are expected to persist after allergen exposure. The aim of the study was to compare allergen-induced changes in eNO in house dust mite sensitized patients with asthma and patients with perennial rhinitis without asthma symptoms. METHODS: Bronchial allergen challenge was performed in 52 patients sensitized to house dust mite (Dermatophagoides pteronyssinus), of whom 26 had non-asthmatic rhinitis and 26 had asthma. Levels of eNO were measured before and 1 h, 1 day and 1 week after challenge. RESULTS: At baseline eNO was significantly lower in non-asthmatic rhinitis compared with asthma (geometric mean eNO (SEM): 121 (1.1) in non-asthmatic rhinitis vs 197 (1.1) nl/min in asthma, P < 0.006). However, the increase in eNO after bronchial allergen challenge in non-asthmatic rhinitis, in particular in those patients with a dual asthmatic response, significantly exceeded the increase in asthma resulting in similar levels of eNO after challenge (geometric mean eNO (SEM) at 24 h postchallenge 204 (1.1) in non-asthmatic rhinitis vs 244 (1.1)nl/min in asthma, P = 0.3). CONCLUSION: The difference in eNO between non-asthmatic rhinitis and asthma at baseline is abolished after allergen exposure due to a significantly greater increase in eNO in non-asthmatic rhinitis.

Administration, Inhalation↗

Allergen-induced bronchial inflammation in house dust mite-allergic patients with or without asthma.

BACKGROUND: It is presently unknown which factors determine the occurrence and persistence of asthma in house dust mite-allergic individuals. The level of allergen-specific IgE antibodies does not seem to be decisive for asthmatic symptoms. Moreover, levels of exposure to mite allergens do not seem to differ significantly between asthmatic and non-asthmatics individuals. AIM: It was hypothesized that the presence or absence of asthmatic symptoms in house dust mite-allergic patients is associated with quantitative or qualitative differences in the cellular bronchial inflammatory response during the late phase of the allergic reaction. This hypothesis was tested in the bronchial allergen challenge model. MATERIAL AND METHODS: Whole lung challenges with house dust mite extract were performed in 52 house dust mite-allergic subjects, of whom 26 had asthma and 26 had perennial rhinitis without asthmatic symptoms. Primary outcomes were parameters for bronchial inflammation in serial samples of induced sputum (cell differentials, eosinophil cationic protein (ECP), interleukin-8 (IL-8), myeloperoxydase (MPO)). In addition, lung function, non-specific bronchial hyper-responsiveness and serial blood samples (eosinophils and IL-5) were analysed. RESULTS: At baseline sputum eosinophils and ECP were similar in both groups but neutrophils and IL-8 were higher in asthmatics. The early bronchoconstriction after allergen challenge was similar in asthma and non-asthmatic rhinitis (median decrease in FEV1: asthma -31.7% vs. non-asthmatics -29.1%, P > 0.1). The late phase bronchoconstriction was significantly greater in asthma (median decrease in FEV1: asthma -27.6% vs. non-asthmatics -18.9%, P = 0.02). Induction of bronchial hyper-responsiveness was similar in both groups. Bronchial allergen challenge elicited significant increases in sputum eosinophils and ECP, which were indistinguishable for both groups (P > 0.1 and P = 0.07, respectively). In contrast, higher numbers of neutrophils persisted in asthma 24h after challenge and were accompanied by significant increases in IL-8 and MPO, which were absent in non-asthmatics (difference between groups P = 0.007 and P = 0.05, respectively). CONCLUSION: Allergen challenge inducedvery similar increases in eosinophils and ECP in induced sputum in allergic asthmatics and in allergic non-asthmatic patients. The difference in bronchial inflammation between asthma and non-asthmatic rhinitis appeared to be more closely related to indices for neutrophilic inflammation.

Adolescent↗

[Non-specific inflammation of the respiratory tract in a female patient with inflammatory bowel disease and osteoporosis].

A 33-year-old woman presented with a non-specific inflammation of the respiratory passages, which occurred two months after partial colectomy and sigmoidectomy for local stenosis caused by an unclassified inflammatory bowel disease. After other causes of the respiratory symptoms had been ruled out, it was concluded that these were a complication of the bowel disease. Due to the osteoporosis, the patient was given a prolonged treatment with high doses of inhaled corticosteroids instead of systemic corticosteroids. She was treated successfully.

Administration, Inhalation↗

Der p 1 and Der p 2 induce less severe late asthmatic responses than native Dermatophagoides pteronyssinus extract after a similar early asthmatic response.

BACKGROUND: The models for exposure to house dust in research and clinical practice are selected with respect to their role in IgE-mediated immediate hypersensitivity. The use of isolated major allergens instead of complex allergen extracts is becoming increasingly popular as it offers some important advantages for quantitative measures in diagnosis and research. OBJECTIVE: To compare house dust mite extract and isolated mite major allergens with respect to their ability to induce early and late asthmatic responses and bronchial hyperreactivity. METHODS: Bronchial responses to house dust mite (HDM, Dermatophagoides pteronyssinus) extract and isolated major allergens from HDM (Der p 1 and Der p 2) were compared in a double-blind, randomized, cross-over study in 20 patients with mild to moderate asthma who were allergic to HDM. Allergen was titrated to a standardized early asthmatic response. Bronchial hyper-responsiveness to histamine (PC20histamine) was determined before and after allergen inhalation to assess allergen-induced bronchial hyper-responsiveness and IL-5 was measured in serum. In addition, the allergens were applied in intracutaneous skin tests and activation of basophil leucocytes and proliferation of peripheral blood mononuclear cells was tested in vitro. RESULTS: After a similar early asthmatic response (mean Deltaforced expiratory volume in 1 s (FEV1),max -29.4 (SD 7.2) vs. -33.1 (8.6) %; mean difference 3.6 (95% CI -0.9 to 8.2) %), the late asthmatic response (mean DeltaFEV1,max -45.9 (21.9) vs. -32.7 (22.3) %; mean difference 13.2 (3.8-22.3) %), the degree of allergen-induced bronchial hyper-responsiveness (mean DeltaPC20histamine, 1.8 (1.0) vs. 1.2 (0.9) doubling dose; mean difference 0.6 (0.2-1.1) doubling dose) and serum IL-5 at 6 h were found to be significantly higher after bronchial challenge with HDM extract than after challenge with an isolated HDM major allergen. Likewise, there was an increased late skin reaction with HDM compared with isolated major allergen after a similar early skin reaction. CONCLUSION: Constituents of HDM extract, other than Der p 1 or Der p 2, with no significant influence on the IgE-mediated early asthmatic response contribute significantly to the allergen-induced late asthmatic response and bronchial hyper-reactivity.

Adolescent↗

Interstitial lung disease induced by exogenous agents: factors governing susceptibility.

The purpose of this review is to describe the present state of knowledge regarding host susceptibility factors that may determine the occurrence, development and severity of interstitial lung disease (ILD) caused by exogenous agents. First, host susceptibility may pertain to differences in the delivery and/or persistence of the noxious agent in the lung. The deposition and clearance of inhaled particles or fibres may vary depending on innate anatomical or physiological characteristics, and on acquired changes, such as nasal disease or smoking-induced alterations. Genetically- or environmentally-induced interindividual differences in the expression of pulmonary biotransformation enzymes may form the basis for, or contribute to the risk of, drug-induced interstitial lung disease. Secondly, there are genetic and acquired variations in various enzymatic and nonenzymatic defence systems that protect cells and tissues against oxidative stress, which is often involved in the pathogenesis of interstitial lung disease caused by particles, fibres, metals, organic agents and drugs. Thirdly, the occurrence of immunological sensitization is dependent on both genetic and environmental factors. This has been demonstrated in chronic beryllium lung disease and in hypersensitivity pneumonitis. Fourthly, the propensity of individuals to develop particular types of inflammation, such as granulomas, is probably under genetic control. The regulation and resolution of inflammation and fibrogenesis caused by dust particles are also partly determined by genetic factors, involving cytokine networks and growth factors. In conclusion, although the issue of genetics pervades the entire discussion of host susceptibility, genes are not the only determinants of health and disease. Environmental factors may be equally important in shaping host susceptibility. Therefore, research must be focused on both the genetic bases and the environmental determinants of interstitial lung disease, in order to provide mechanism-based prevention strategies, early detection of, and improved therapy for these conditions.

Air Pollutants↗

Methodological aspects in the analysis of spontaneously produced sputum.

Analysis of sputum as a specimen containing inflammatory indices has gained considerable interest during the last decade with focus on chronic bronchitis (CB) with or without airway obstruction, cystic fibrosis (CF), chronic obstructive pulmonary disease (COPD) and asthma. The nature of the specimens requires expert skill for handling them and for performing analyses. The analysis of spontaneously produced sputum has been performed less frequently than that of induced sputum. This is surprising as several studies have shown that the collection procedures and the assay methods are highly reproducible. There are several valid parameters of sputum analysis that can be applied in research on airway inflammation and in monitoring therapy of patients. Spontaneously produced sputum can be obtained in a simple and non-invasive way, which warrants further efforts to expand the range of applications of its analysis. Here, we will critically review the procedures for collecting spontaneously produced sputum, for handling the samples, and the requirements for assay of sputum components. This will imply the reproducibility of the analysis, the recovery of solutes, the validity of assays in terms of reproducibility and of linearity of the response, the validity of the assays with respect to association with other inflammatory parameters and with clinical parameters, and the usefulness of assays with respect to their response upon treatment of patients.

Biomarkers↗

[Immunology in medical practice. XXIX. Pathogenesis of allergic and immunologic pulmonary diseases].

Recently acquired insights into the complex functions of the immune system in the airways and lungs shed new light on the importance of local immunologic defence mechanisms in the maintenance of a normal lung function. Prolonged exposure to inhaled allergens or to aspecific injurious substances in the environment, in particular, may give rise to the onset of immunopathology that may manifest itself only years later. Clinically, the most common of such diseases is allergic asthma. This results from the interaction of an unknown number of genes with specific and aspecific environmental factors. In chronic obstructive pulmonary disease, exposure to such aspecific factors (cigarette smoking) is the most important aetiological factor. Immune-mediated diseases may also develop in the presence of congenital or acquired immunodeficiencies and in idiopathic diffuse pulmonary disorders. In addition, pulmonary disease is often a component of collagen diseases, occupational diseases and idiopathic pulmonary fibrosis. Recently developed investigational techniques such as bronchoalveolar lavage (BAL), cloning experiments on cells obtained by BAL, and ex vivo studies on cytokine production patterns are making an important contribution to the acquired understanding of the immunopathogenesis of pulmonary diseases.

Acute-Phase Reaction↗

IL-6 protein production by airway epithelial(-like) cells disabled in IL-6 mRNA degradation.

IL-6 mRNA and protein expression in human airway epithelial-like H292 cells depends on rapid, but regulable IL-6 mRNA degradation. We restricted IL-6 mRNA degradation by partially inhibiting protein synthesis and studied the IL-6 response. Despite partial inhibition of protein synthesis, IL-6 protein production was increased and prolonged. Furthermore, the threshold concentration for stimuli of IL-6 protein production decreased and the dose-response curves became steeper. Similar findings were obtained with primary human bronchial epithelial cells. This exaggerated production may apply to other proteins encoded by labile mRNA and is likely to occur during viral infection of airway epithelial cells.

Cells, Cultured↗

Double staining of intracellular cytokine proteins and T-lymphocyte subsets. Evaluation of the method in blood and bronchoalveolar lavage fluid.

An immunocytochemical staining method has been developed for simultaneous staining of both cell surface markers (CD4 and CD8) and intracellular cytokine proteins IFN-gamma, IL-4 and IL-5. Cell surface molecules were visualized with alkaline phosphatase, which was developed by Fast Blue BB. Intracellular cytokine proteins were detected by amino-ethyl carbazole. We applied this technique to T cells from T-cell lines and T-cell clones, peripheral blood mononuclear cells and broncho-alveolar lavage fluid cells. Cells were used either unstimulated or stimulated for 4 h with 1 ng/ml PMA and 1 microg/ml ionomycin, which proved to be an optimal stimulus taking cytokine staining, cell recovery and cell viability into account. We studied peripheral blood mononuclear cells from healthy subjects and found that without in vitro stimulation on average 0.4% of the cells were IFN-gamma positive cells. In unstimulated broncho-alveolar lavage fluid cells of the 2 allergic asthmatic subjects studied so far we found higher numbers of cytokine-positive cells (up to 22% of the lymphocytes being IL-4+ cells). By in vitro stimulation, the numbers of cytokine-positive peripheral blood mononuclear cells from the healthy subjects were increased to maximally 5% IFN-gamma+ cells. In stimulated lavage fluid cells from allergic asthmatic subjects maximally 34% of the lymphocytes became IFN-gamma+. We conclude that this method allows detection of intracellular cytokine proteins in both CD4+ and CD8+ T cells without the need for stimulating the cells in vitro. In vitro stimulation may change the cytokine profile detected.

Adult↗