Methacholine Chloride: A quaternary ammonium parasympathomimetic agent with the muscarinic actions of ACETYLCHOLINE. It is hydrolyzed by ACETYLCHOLINESTERASE at a considerably slower rate than ACETYLCHOLINE and is more resistant to hydrolysis by nonspecific CHOLINESTERASES so that its actions are more prolonged. It is used as a parasympathomimetic bronchoconstrictor agent and as a diagnostic aid for bronchial asthma. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1116)
A number of mechanisms have been proposed as the basis for the relationship between nonspecific airway responsiveness and prechallenge pulmonary function. Because resistance to flow through a tube is inversely proportional to the radius to the fourth power, a given degree of bronchoconstrictor-induced circumferential airway narrowing can be expected to cause a proportionally larger increase in airway resistance in a narrow airway than in a wider airway. Intersubject differences in the distribution of resistance along the bronchial tree may influence both the pattern of aerosol deposition and the relative impact on total airway resistance of bronchoconstriction at particular sites such as the peripheral airways. Airway hyperresponsiveness may result in heightened bronchomotor tone prior to challenge and thereby be correlated with reduced prechallenge pulmonary function. The convention of expressing responsiveness in terms of percentage of change in FEV, (eg, PD20FEV,) imposes a mathematical ...
The 547 asymptomatic subjects with normal pulmonary function were grouped according to quintile of prechallenge FEV, (percent predicted), and the fifth percentiles of PD20FEV, within each quintile of FEV, were calculated (Table 2). The fifth percentile of methacholine PD20FEV, increased with increasing quintile of prechallenge FEV,. This relationship is shown graphically in Figure 1, in which the fifth percentile of PD20FEV, for each quintile is plotted against the median FEV, for that quintile. Restricting analysis to a subgroup of 157 lifetime nonsmokers yielded similar values for the fifth percentiles of PD20FEV,, for both overall and FEV,-specific percentiles (data not shown). canadian health & care mall. The overall fifth percentile of PD20FEV, (8.3 (imol) and the FEV,-specific fifth percentiles of PD20FEV, (as indicated in Table 2) respectively defined the 26 (4.8 percent) and 27 (4.9 percent) most responsive subjects among the 547 asymptomatic men. Seventeen (3.1 percent) men were ...
Since in the model used in this study all the Newtonian resistive and inertial properties are represented by Raw and Iaw , respectively, the inferences to central and peripheral airway responses are not straightforward. However, the significant increase in Iaw at PCFEV0.5 provides indirect evidence that Mch evoked significant constriction in the nasal and central airways. In addition, nine infants had a significant positive response in Iaw as defined by an increase of ,2 SD units. The inertance of the nasal passages contributes most of the total inertance of the respiratory system,16 making this parameter highly sensitive to changes in the properties of the extrathoracic airways. This response of both the central and peripheral airways to inhaled Mch has also been shown in asymptomatic adults by Ohrui et al 17 using a catheter tipped manometer lodged in a bronchus of 3 mm inner diameter. The response in Iaw in the present study indicates a response in the nasal and/or central pathways. Such a ...
Dr. Anand responded: Methacholine test. The test result is available as soon as the test is completed. It can take half to one hour. A physician has to interpret the test results. Some times the answer may not be clear cut.
TY - JOUR. T1 - Investigative bronchoprovocation and bronchoscopy in airway diseases. AU - Busse, William W.. AU - Wanner, Adam. AU - Adams, Kenneth. AU - Reynolds, Herbert Y.. AU - Castro, Mario. AU - Chowdhury, Badrul. AU - Kraft, Monica. AU - Levine, Robert J.. AU - Peters, Stephen P.. AU - Sullivan, Eugene J.. PY - 2005/10/1. Y1 - 2005/10/1. N2 - Rationale: Basic and clinical research strategies used for many lung diseases have depended on volunteer subjects undergoing bronchoscopy to establish access to the airways to collect biological specimens and tissue, perhaps with added bronchoprovocation in asthma syndromes. These procedures have yielded a wealth of important scientific information. Since the last critical review more than a decade ago, some of the techniques and applications have changed, and untoward events have occurred, raising safety concerns and increasing institutional review scrutiny. Objectives and Methods:To reappraise these investigational methods in the context of ...
Smiths Medical Asthma Patient Testing Kit (Methacholine Bronchoprovocation) is a convenient, all-inclusive procedural kit for the assessment of the respiratory
No significant alterations in airway reactivity were observed at one or seven days after exposure either in baseline values or following methacholine (MCh) inhalation challenge. Although there was a trend for an increase in lung neutrophils and phagocyte oxidant production at one-day post exposure, there were no significant differences in parameters of lung inflammation. In addition, increased blood monocytes and neutrophils, and decreased lymphocyte numbers at one-day post exposure also did not differ significantly from air controls, and no alterations in splenocyte populations, or serum or spleen immunoglobulin M (IgM) to antigen were observed. There were no significant differences in peripheral vascular responsiveness to vasoconstrictor and vasodilator agonists or in blood pressure (BP) responses to these agents; however, the baseline heart rate (HR) and HR responses to isoproterenol (ISO) were significantly elevated at one-day post exposure, with resolution by day 7 ...
Deep Inspiration Breath Hold (DIBH) is a simple technique used to treat cancer in the breast or chest wall. Its precisely targeted so theres less chance of damage to the heart and lungs. ...
Detailed dosage guidelines and administration information for Provocholine (methacholine chloride). Includes dose adjustments, warnings and precautions.
Our study made a preliminary demonstration that the finding of obstruction based on the FEV1/FVC in the setting of a normal FEV1 (defined in this study as greater than 90% of predicted) does not consistently represent a normal physiologic variant. Nearly 28% of tested patients met criteria for AHR by either BD response or bronchoprovocation testing, irrespective of the presence or absence of symptoms. While there were no significant differences in AHR for those patients with an FEV1 , 100% of predicted versus ≥ 100% of predicted, the overall trend demonstrated a decreased frequency of AHR for an FEV1 ≥ 100% of predicted, as 80% of patients with evidence of AHR had an FEV1 , 100%. This becomes important in correlating the clinical suspicion for underlying disease with the indication (screening vs symptomatic) for PFT. Conversely, even in the presence of active pulmonary symptoms or established diagnoses, nearly 75% of patients tested did not demonstrate a significant BD response. This might ...
Bronchoprovocation challenge testing is sometimes used to diagnose asthma if your lung function is normal but you have typical asthma symptoms.
Addressing the issue of whether to grant a second inter partes review (IPR) after all of the claims had previously been adjudicated, the Patent Trial…
Rationale: Methacholine and mannitol challenges are used clinically to assess airway hyperresponsiveness (AHR). Cough during (a) high-dose methacholine challenge in individuals with methacholine-induced cough and normal airway sensitivity and (b) mannitol challenge in some individuals with asthma both occur in the absence of significant declines in forced expiratory volume in one second (FEV1). We hypothesized mechanical responses to these challenges would reflect a continuum amongst subjects with: (i) asthma; (ii) cough variant asthma (CVA) and (iii) methacholine-induced cough and normal airway sensitivity due to varying degrees of impairment/preservation of the beneficial effects of deep inspirations. Purpose: To compare cough and airway responses to mannitol and high-dose methacholine challenges between these groups. Methods: Individuals with asthma or suspected CVA were invited to participate. Subjects were challenged with mannitol and high-dose methacholine in random order 2-14 days apart. ...
P.H. Howarth, J.S. Mann, S.T. Holgate; The Influence of Resting Airway Calibre on Non-Specific and Specific Airway Reactivity in Asthma. Clin Sci (Lond) 1 January 1984; 67 (s9): 5P-6P. doi: https://doi.org/10.1042/cs067005Pb. Download citation file:. ...
TY - JOUR. T1 - Assessment of bronchial responsiveness following exposure to inhaled occupational and environmental agents. AU - Currie, G. P.. AU - Ayres, Jonathan Geoffrey. PY - 2004. Y1 - 2004. M3 - Article. VL - 23. SP - 75. EP - 81. JO - Toxicology. JF - Toxicology. SN - 0300-483X. ER - ...
Dose-response curves to methacholine were examined in 9 normal and 10 asthmatic volunteers to determine whether the relationship between dose and response can be adequately summarized by means of a single, continuous measure that is not censored at lower levels of bronchial responsiveness. Subjects …
The IUPHAR/BPS Guide to Pharmacology. methacholine ligand page. Quantitative data and detailed annnotation of the targets of licensed and experimental drugs.
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TY - JOUR. T1 - Methacholine inhalation challenge studies in a selcted pediatric population. AU - Hopp, R. J.. AU - Bewtra, A. K.. AU - Nair, N. M.. AU - Watt, G. D.. AU - Townley, R. G.. PY - 1986. Y1 - 1986. N2 - To determine bronchial reactivity patterns, 400 subjects, 5 to 21 yr of age, underwent a methacholine challenge in a Natural History of Asthma study. The diagnosis of asthma or allergy was based on a respiratory questionnaire. Subjects were nonsmokers and had had no respiratory infections for 1 month. Intradermal skin tests were done. The methacholine challenge response was expressed as the area beneath the dose-response curve (Area35). Fifty-five asthmatics, 113 normal subjects from normal families, 103 normal subjects from asthma families, 60 normal twins, and 69 allergic subjects without asthma were studied. Overall, 52% of nonasthmatics and 47% of nonallergic subjects had an Area35 less than 4,000 (800 breath units). There was a difference (p , 0.05) in the distribution of ...
Bronchial hyperresponsiveness (or other combinations with airway or hyperreactivity) is a state characterised by easily triggered bronchospasm (contraction of the bronchioles or small airways). Bronchial hyperresponsiveness can be assessed with a bronchial challenge test. This most often uses products like methacholine or histamine. These chemicals trigger bronchospasm in normal individuals as well, but people with bronchial hyperresponsiveness have a lower threshold. Bronchial hyperresponsiveness is a hallmark of asthma but also occurs frequently in people suffering from chronic obstructive pulmonary disease (COPD). In the Lung Health Study, bronchial hyperresponsiveness was present in approximately two-thirds of patients with non-severe COPD, and this predicted lung function decline independently of other factors. In asthma it tends to be reversible with bronchodilator therapy, while this is not the case in COPD. Bronchial hyperresponsiveness has been associated with gas cooking among subjects ...
TY - JOUR. T1 - Dosimetric Considerations in Respiratory-Gated Deep Inspiration Breath-Hold for Left Breast Irradiation. AU - Walston, Steve. AU - Quick, Allison M.. AU - Kuhn, Karla. AU - Rong, Yi. PY - 2017/1/1. Y1 - 2017/1/1. N2 - Purpose: To present our clinical workflow of incorporating AlignRT for left breast deep inspiration breath-hold treatments and the dosimetric considerations with the deep inspiration breath-hold protocol. Material and Methods: Patients with stage I to III left-sided breast cancer who underwent lumpectomy or mastectomy were considered candidates for deep inspiration breath-hold technique for their external beam radiation therapy. Treatment plans were created on both free-breathing and deep inspiration breath-hold computed tomography for each patient to determine whether deep inspiration breath-hold was beneficial based on dosimetric comparison. The AlignRT system was used for patient setup and monitoring. Dosimetric measurements and their correlation with chest wall ...
Bronchial hyperresponsiveness (or other combinations with airway or hyperreactivity) is a state characterised by easily triggered bronchospasm (contraction of the bronchioles or small airways).. Bronchial hyperresponsiveness can be assessed with a bronchial challenge test. This most often uses products like methacholine or histamine. These chemicals trigger bronchospasm in normal individuals as well, but people with bronchial hyperresponsiveness have a lower threshold.. Bronchial hyperresponsiveness is a hallmark of asthma but also occurs frequently in people suffering from chronic obstructive pulmonary disease (COPD). In the Lung Heart Study, bronchial hyperresponsiveness was present in approximately two-thirds of patients with non-severe COPD, and this predicted lung function decline independently of other factors. In asthma it tends to be reversible with bronchodilator therapy, while this is not the case in COPD. ...
Cough is a common, disruptive and at times disabling symptom which often prompts patients to seek medical attention. Determining the cause(s) of chronic cough can be challenging, and costly. Asthma and other airway disorders are among the most common causes of chronic cough; and cough can be the sole symptom of asthma. Little is known about why some patients with asthma primarily cough and do not develop the other symptoms of asthma such as shortness of breath or wheeze. Improved understanding of the reasons for these different manifestations may lead to new and more effective treatment strategies. We have notices differences in pressure measurements inside the chest in patients who mostly cough during induced bronchoconstriction, which might be part of the explanation for varying symptoms. This study will compare lung mechanical responses during methacholine and mannitol-induced induced airway narrowing between typical asthma, cough variant asthma (CVA) and an airway inflammatory disorder that ...
Cough is a common, disruptive and at times disabling symptom which often prompts patients to seek medical attention. Determining the cause(s) of chronic cough can be challenging, and costly. Asthma and other airway disorders are among the most common causes of chronic cough; and cough can be the sole symptom of asthma. Little is known about why some patients with asthma primarily cough and do not develop the other symptoms of asthma such as shortness of breath or wheeze. Improved understanding of the reasons for these different manifestations may lead to new and more effective treatment strategies. We have notices differences in pressure measurements inside the chest in patients who mostly cough during induced bronchoconstriction, which might be part of the explanation for varying symptoms. This study will compare lung mechanical responses during methacholine and mannitol-induced induced airway narrowing between typical asthma, cough variant asthma (CVA) and an airway inflammatory disorder that ...
The results of this study demonstrate the bronchodilator and bronchoprotective effects of acute administration of both the short-acting β2‐agonist terbutaline and the long-acting β2‐agonist formoterol. A significant improvement in FEV1 30 min after each active treatment and a dose-dependent reduction in AR to both AMP and histamine following formoterol was observed. The two higher doses of formoterol produced a greater bronchoprotective effect against AMP compared to that against histamine, whereas 6‐µg formoterol and 500-µg terbutaline reduced AR to both spasmogens to a similar extent.. The similarity between AMP and histamine dose/response curves following placebo and each active treatment allows direct comparison of the bronchoprotection against each spasmogen. Thus, to explain the findings, it is likely that there are additional mechanisms to β2‐agonist-mediated functional antagonism against induced airway smooth muscle contraction. The greater degree of bronchoprotection ...
Local Lung Function And Airway Size Response During Methacholine Challenge And Salbutamol Treatment Measured Using High-Resolution Dynamic CT And Functional Lung Imaging
The aim of this study was to assess the effectiveness of an asthma prevalence video questionnaire, a standard written questionnaire based on the IUATLD Bronchial Symptoms Questionnaire and a new written questionnaire designed for an international study of asthma and allergies in childhood ISAAC in predicting bronchial hyper-responsiveness BHR...
TY - JOUR. T1 - Histamine forming capacity (HFC) and its modulation by H3 receptor ligands in a model of bronchial hyper-responsiveness. AU - Allen, Marcus. AU - Graham, P.. AU - Morris, G.. PY - 1996/3/1. Y1 - 1996/3/1. M3 - Article. VL - 45. SP - 118. EP - 122. JO - Inflammation Research. JF - Inflammation Research. SN - 1023-3830. IS - 3. ER - ...
Bronchial hyperresponsiveness (BHR) is a hallmark of asthma. BHR to methacholine is used for diagnosis, but the role in monitoring treated asthma is not established. In the present study we assessed the relation between BHR to methacholine, airways inflammation, asthma control and symptoms.. Methacholine challenge and FeNO measurements were done in 371 asthmatics (aged 10-35 years) with inhaled corticosteroids prescribed. PD20 ,0.3 mg defined moderate-severe BHR, 0.3 to 1.0 mg borderline-mild BHR, and ,1.0 mg normal response (Schulze et al. Resp Med 2009). Well-controlled asthma (≥20 in Asthma Control Test) was found in 68% of children (,18 years) and 75% of adults (≥18 years). All subjects answered questions on asthma symptoms.. Moderate-severe BHR was found in 61% of children and 44% of adults. FeNO increased with more severe BHR in both children and adults, with a higher explanatory value in children (R2=0.15 vs 0.06). Well-controlled asthma was less prevalent in the moderate-severe BHR ...
in International Journal of Clinical Practice (2012), 66(2), 158-65. Background: Asthma diagnosis is based on the presence of symptoms and the demonstration of airflow variability. Airway inflammation measured by fractional exhaled nitric oxide, measured at a flow rate of ... [more ▼]. Background: Asthma diagnosis is based on the presence of symptoms and the demonstration of airflow variability. Airway inflammation measured by fractional exhaled nitric oxide, measured at a flow rate of 50 ml/s (FE(NO50) ) remains a controversial diagnostic tool. Aim: To assess the ability of FE(NO50) to identify bronchial hyperresponsiveness (BHR) to methacholine (provocative concentration of methacholine causing a 20% fall in FEV(1) ; PC20M ,/= 16 mg/ml) and to establish whether or not symptoms relate to FE(NO50) and PC20M in patients with no demonstrated reversibility to beta(2) -agonist. Methods: We conducted a prospective study on 174 steroid naive patients with respiratory symptoms, forced expiratory ...
TY - JOUR. T1 - Airway hyperresponsiveness. T2 - From molecules to bedside. AU - Sieck, Gary C. PY - 2003/7/1. Y1 - 2003/7/1. UR - http://www.scopus.com/inward/record.url?scp=0038309533&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=0038309533&partnerID=8YFLogxK. M3 - Article. C2 - 12794089. AN - SCOPUS:0038309533. VL - 95. SP - 1. EP - 2. JO - Journal of Applied Physiology. JF - Journal of Applied Physiology. SN - 8750-7587. IS - 1. ER - ...
In order to diagnose and monitor asthma, your healthcare provider examines you. He or she listens to your chest and asks you to breathe. You are asked questions about your symptoms, triggers, and any family history of asthma or allergies. Special lung function tests may also be done. One of these is called a spirometry test.. ...
Rationale: In asthma, airway inflammation, obstruction and reactivity may lead to ventilation heterogeneity; our understanding of this process is limited in asthmatic chi..
Page 2 - Im not sure if this in the literature or not (probably) and I havent really studied it yet, but... If you have a 10kg kid with bronchospasm, what would you treatment be. Im imagining, that in
It was recently reported that caffeine may reduce the clinical symptoms of asthma and may prevent the clinical manifestations of this disease. The effect of caffeine on histamine responsiveness is unknown. The effect of caffeine (5 mg/kg) and placebo on histamine responsiveness (the provocation concentration causing a 20% fall in FEV1, PC20) was studied in 10 subjects with mild asthma (prechallenge FEV1 84% of predicted value). The PC20 for histamine bronchoprovocation after caffeine ingestion was 2.65 (95% confidence limits 0.99, 7.10) mg/ml. After placebo the PC20 was 1.89 (0.96, 3.71) mg/ml. It is concluded that caffeine in a dose equivalent to about three cups of coffee has a very small effect, if any, on histamine bronchoprovocation in those with mild asthma. Specific instructions about not having drinks containing caffeine before histamine challenge are therefore not necessary.. ...
Wheezing during infancy has been linked to early loss of pulmonary function. We prospectively investigated the relation between bronchial hyperresponsiveness (BHR) and progressive impairment of pulmonary function in a cohort of asthmatic infants followed until age 9 years. We studied 129 infants who had had at least three episodes of wheezing. Physical examinations, baseline lung function tests and methacholine challenge tests were scheduled at ages 16 months and 5, 7 and 9 years. Eighty-three children completed follow-up. Twenty-four (29%) infants had wheezing that persisted at 9 years of age. Clinical outcome at age 9 years was significantly predicted by symptoms at 5 years of age and by parental atopy. Specific airway resistance (sRaw) was altered in persistent wheezers as early as 5 years of age, and did not change thereafter. Ninety-five per cent of the children still responded to methacholine at the end of follow-up. The degree of BHR at 9 years was significantly related to current clinical status
STUDY OBJECTIVE: This study examined the impact on childrens respiratory health of a government air quality intervention that restricted the sulphur content of fuels to 0.5% from July 1990 onwards. DESIGN/SETTING/PARTICIPANTS: This study examined the changes, one and two years after the introduction of the intervention, in airway hyperreactivity of non-asthmatic and non-wheezing, primary 4, 5, and 6, school children aged 9-12 years living in a polluted district compared with those in a less polluted district. Bronchial hyperreactivity (BHR)(a 20% decrease in FEV1 provoked by a cumulative dose of histamine less than 7.8 mumol) and bronchial reactivity slope (BR slope) (percentage change in logarithmic scale in FEV1 per unit dose of histamine) were used to estimate responses to a histamine challenge. The between districts differences after the intervention were studied to assess the effectiveness of the intervention. MAIN RESULTS: In cohorts, comparing measurements made before the intervention ...
Wilson, AM, Gray, RD, Hall, IP and Lipworth, BJ (2006) The effect of beta2-adrenoceptor haplotypes on bronchial hyper-responsiveness in patients with asthma. Allergy, 61 (2). pp. 254-259. ISSN 1398-9995 Full text not available from this repository. (Request a copy ...
We obtained dynamic and flow-interrupted (quasi-static) pressure-volume loops from the lungs of anesthetized paralyzed open-chest mongrel dogs by measuring tracheal flow and pressure and alveolar pressure (PA) in three different regions using alveolar capsules. We used continuous tidal ventilation to obtain dynamic PA-volume loops and used the single-breath-interrupter technique to construct quasi-static pressure-volume loops for the same tidal volume (VT). We used three different VTs (15 and 20 ml/kg and inspiratory capacity) under control conditions and a VT of 15 ml/kg after methacholine-induced bronchoconstriction. We found that quasi-static hysteresis was negligible under control conditions for VT of 15 and 20 ml/kg. Quasi-static hysteresis became more important (36 +/- 11% of the corresponding dynamic PA-volume loop) during inspiratory capacity ventilation and after induced bronchoconstriction (27 +/- 12% of the corresponding dynamic PA-volume loop). We conclude that during tidal ...
The effectiveness of strategies for treatment of the altered static lung volume and against the development of bronchial hyperreactivity (BHR) following a left ventricular dysfunction (LVD) induced by myocardial ischaemia was investigated in a rat model of sustained postcapillary pulmonary hypertension. Airway resistance (Raw) was identified from the respiratory system input impedance (Zrs) in four groups of rats. End-expiratory lung volume (EELV) was determined plethysmographically, and Zrs was measured under baseline conditions and following iv infusions of 2, 6 or 18 μg/kg/min methacholine. Sham surgery was performed in the rats in Group C, while the left interventricular coronary artery was ligated and Zrs and its changes following identical methacholine challenges were reassessed in the same rats 8 weeks later, during which no treatment was applied (Group I), or the animals were treated daily with a combination of an angiotensin enzyme converter inhibitor and a diuretic (enalapril and furosemide,
CiteSeerX - Scientific documents that cite the following paper: Diesel exhaust enhances airway responsiveness in asthmatic subjects
It is not appropriate for Drs Kaplan and Stanbrook to suggest that physicians who do not use spirometry should not manage patients with asthma.1 Such comments do not provide constructive guidance about clinical management and might serve to challenge the central role of family physicians in asthma care. Interestingly, it appears that Kaplan and Stanbrook are now supporting my side of the debate. They state that "empiric treatment of presumed asthma is acceptable only if followed by objective measurements of lung function to confirm clinical suspicion." This position seems very similar to my suggestion to treat and refer for methacholine challenge testing, as this approach will identify most patients with suspected asthma.2. My colleagues appropriately highlight that a single spirometry test might not always be successful in diagnosing or ruling out asthma definitively, but they offer no practical strategy for how physicians should manage patients with suspected asthma but normal spirometry ...
2016 (English)In: Upsala Journal of Medical Sciences, ISSN 0300-9734, E-ISSN 2000-1967, Vol. 121, no 3, p. 198-198Article in journal, Letter (Refereed) Published ...
Tampa, Florida (PRWEB) July 15, 2014 -- Acoustiblok was recently featured on the new National Geographic Channel series, Showdown of the Unbeatables. The
Learn Big History: Connecting Knowledge from Macquarie University. We currently face unprecedented challenges on a global scale. These problems do not neatly fall into disciplines. They are complicated, complex, and connected. Join us on this ...
A thriving and open Internet provides the foundation for the fourth industrial revolution. There has been growing concern that the Internet may be in danger of splintering into a series of bordered cyberspace segments endangering its very nature. World Economic Forums Global Challenge on the Future of the Internet supported research highlights a number of fault lines that need to be addressed by bringing all stakeholders together.
My humble answer: There really is no difinitive test to diagnose asthma. However, the methacholine challenge is a pretty significant indicator. If you have a negative methacholine challenge chances are you dont have asthma. The reason I can say this is because if you have asthma the challenge will make you short of breath, and a bronchodilator breathing treatment will make you feel better. If none of these happen, chances are you dont have asthma. A second opinion is always a good idea, however. ...
TY - JOUR. T1 - Effects of overexpression of IL-10, IL-12, TGF-β and IL-4 on allergen induced change in bronchial responsiveness. AU - Fu, Chi Ling. AU - Ye, Yi Ling. AU - Lee, Yueh L.. AU - Chiang, Bor Luen. PY - 2006/5/8. Y1 - 2006/5/8. N2 - Background: An increasing prevalence of allergic diseases, such as atopic dermatitis, allergic rhinitis and bronchial asthma, has been noted worldwide. Allergic asthma strongly correlates with airway inflammation caused by the unregulated production of cytokines secreted by allergen-specific type-2 T helper (Th2) cells. This study aims to explore the therapeutic effect of the airway gene transfer of IL-12, IL-10 and TGF-β on airway inflammation in a mouse model of allergic asthma. Methods: BALB/c mice were sensitized to ovalbumin (OVA) by intr aperitoneal injections with OVA and challenged by nebulized OVA. Different cytokine gene plasmids or non-coding vector plasmids were instilled daily into the trachea up to one day before the inhalatory OVA ...
1. Lung function was studied in fifty-six symptom-free asthmatic subjects after the inhalation of urea, an agent not previously used for asthma provocation. The effects of urea were compared with those produced by the inhalation of methacholine and of isoprenaline.. 2. After urea ventilatory capacity was impaired in 68% of subjects and improved in 16%. This response was a relatively constant phenomenon in the same subject. Urea appears to possess the unusual property of being able to produce both bronchoconstriction and bronchodilatation. The response could not be related to any of the clinical or other physiological variables examined.. 3. Mild hypoxaemia, ventilation-blood-flow inequality and impairment of gas transfer also occurred after urea administration.. 4. Methacholine produced considerable impairment of ventilatory capacity with consistent hyperinflation but with variable changes in ventilatory pattern and distribution of ventilation.. 5. Isoprenaline rapidly and completely reversed ...