SEARCH · PubMed Health

Results for “RESPIRATORY TRACT”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 667 records · Page 37Linked to original sources

PubMed1987

[Clinical studies of norfloxacin on respiratory tract infections in aged people].

Norfloxacin (NFLX), an oral antibacterial agent of new quinolone derivative, was administered at daily doses of 300-600 mg t.i.d. to 20 aged patients with respiratory tract infections. The results obtained are summarized as follows. 1. Clinical efficacies were moderate in 6 patients with upper respiratory tract infections, and moderate in 11 patients and fair in 3 patients with lower respiratory tract infections. In the 20 patients, overall clinical efficacies were moderate in 17 patients, hence the efficacy rate was 85%. 2. Bacteriologically, causative organisms were detected in 10 of the 14 cases with lower respiratory tract infections. In these cases, bacteriological responses were "eradicated" in 9 cases, "decreased" in 1 case and "unknown" in 1 case, the rate of eradication was 90%. 3. No adverse reactions or abnormal laboratory test values were observed.

Aged↗

PubMed1999

[The study of E-cadherin expression on injury and repair of epithelium of respiratory tract in smoking mice].

OBJECTIVE: To investigate effects of smoking on E-cadherin (E-cd) expression of injury and repair of respiratory tract epithelium by observation of dynamic expression of E-cd on epithelial cells of respiratory tract in smoking mice. METHODS: Immunohistochemistry SP technique was used to examine E-cd expression on epithelial cells of respiratory tract in smoking mice of different stages and dosages and the morphological changes observed by light and electron microscopy respectively. RESULTS: Four and twelve weeks after smoking, the E-cd expression in the epithelial cells was significantly down-regulated compared with the control group (P < 0.01). Morphologically, the intercellular junction was loose, and the epithelial cells were injured and proliferated on the same time. Eight weeks after smoking, however, the E-cd expression was not different from that of the control group (P > 0.05). CONCLUSIONS: Smoking is able to cause wavy change of the E-cd expression on the epithelial cells which may play an important role in the injury and repair of the epithelial cell of the respiratory tract.

Animals↗

PubMed2004

Immunohistochemical study of the innervation of pulmonary vessels and smooth muscles in the respiratory tract of two frog species.

The innervation of the respiratory tract of amphibians is still poorly understood. Therefore, the respiratory tracts of the frogs Rana esculenta and Discoglossus pictus have been investigated in order to describe non-adrenergic non-cholinergic (NANC) and adrenergic innervation, and the localization of neuromediators that are possibly involved. Immunohistochemical staining of many bioactive substances was found in neuroepithelial cells of the buccopharynx, larynx, lung septa, nerves and neurons throughout the airway system. The findings indicate the occurrence of vasoactive intestinal peptide (VIP)-immunopositive nerve fibers in fibromuscular septa and the vasculature, nitrergic innervation of the large pulmonary veins showing a plexus of nNOS-immunopositive nerve fibers that also innervate the lung wall and the localization of neuronal nitric oxide synthase (nNOS) in neurons in the lung wall. In addition, laryngeal blood vessels and small arteries in the wall of septa that form capillary networks are supplied by enkephalin-immunopositive nerve terminals. We conclude that the airway system of the two frog species studied is innervated by a parasympathetic NANC system. Adrenergic innervation was also found that was immunostained for tyrosine hydroxylase. Adrenergic fibers were mainly present in muscles in septal edges, arteries present in septa and the wall of the lung. It is suggested that nNOS-positive and leu-enkephalin-positive neurons mediate vasodilation via the release of NO, but the nature of the NANC innervation remains obscure. Despite the many pharmacological studies of the lungs of amphibians, the physiological role of pulmonary autonomic innervation remains poorly understood.

Animals↗

PubMed2002

Efficacy and acceptability of fusafungine, a local treatment for both nose and throat infections, in adult patients with upper respiratory tract infections.

The objective of this study was to assess the effectiveness and acceptability of fusafungine in the treatment of patients with community-acquired, upper respiratory tract infections. These infections, although frequently of viral origin, may be conducive to bacterial superinfection. Fusafungine, a combination of several enniatins, has been shown to display bacteriostatic activity against many micro-organisms responsible for infections of the respiratory tract, along with anti-inflammatory activity. This open, multi-centre study analysed data on 166 patients suffering from upper respiratory tract infections treated for 7 or 10 days with a fusafungine metered-dose spray. The incidence of upper respiratory tract symptoms was significantly reduced from baseline (p < or = 0.001) with the treatment evaluated as excellent or good by 92.1% of physicians. In 77.7% of the patients, no further treatment was necessary at the end of the seven-day therapeutic period. Out of the 37 patients who had the treatment prolonged for three more days, 78.4% had regression of their URTI at the end of therapy. In terms of tolerability, assessment by the investigators and the patients themselves demonstrated that fusafungine was extremely well tolerated. Acceptability of the treatment was considered poor by only one patient. Results of this study suggest that fusafungine, whatever the aetiology of the infection, gives rapid relief of nasal and pharyngeal symptoms and provides strong evidence of its efficacy and acceptability in treating URTIs.

Administration, Intranasal↗

PubMed2005

Adaptation of the ICRP publication 66 respiratory tract model to data on plutonium biokinetics for Mayak workers.

The biokinetics of inhaled plutonium were analyzed using compartment models representing their behavior within the respiratory tract, the gastrointestinal tract, and in systemic tissues. The processes of aerosol deposition, particle transport, absorption, and formation of a fixed deposit in the respiratory tract were formulated in the framework of the Human Respiratory Tract Model described in ICRP Publication 66. The values of parameters governing absorption and formation of the fixed deposit were established by fitting the model to the observations in 530 autopsy cases. The influence of smoking on mechanical clearance of deposited plutonium activity was considered. The dependence of absorption on the aerosol transportability, as estimated by in vitro methods (dialysis), was demonstrated. The results of this study were compared to those obtained from an earlier model of plutonium behavior in the respiratory tract, which was based on the same set of autopsy data. That model did not address the early phases of respiratory clearance and hence underestimated the committed lung dose by about 25% for plutonium oxides. Little difference in lung dose was found for nitrate forms.

Absorption↗

PubMed2001

Symptoms, signs, and prescribing for acute lower respiratory tract illness.

BACKGROUND: Most patients who consult with acute lower respiratory symptoms receive antibiotics, usually without evidence of significant infection. The physical signs at presentation of acute lower respiratory tract illness and the rate at which symptoms resolve and normal activities recover is not well documented. AIM: To examine in patients with lower respiratory tract infection (LRTi), their physical signs at presentation, their relationship to antibiotic prescribing, and symptom resolution and resumption of normal activities. DESIGN OF STUDY: Analysis of data collected prospectively during presentation of acute LRTi in primary care and from patient symptom diary cards. SETTING: Forty GPs who were members of an informal Community Respiratory Infection Interest Group recruited 391 patients to the study. METHOD: Information was collected on pulse, oral temperature, respiratory rate, abnormalities on auscultation, and details of any antibiotic prescription. Patients completed symptom diary cards for the following 10 days. RESULTS: Of the 391 patients who consulted 71% received antibiotics. A minority had abnormal physical signs: 17% had a pulse greater than 90 bpm, 15% a respiratory rate greater than 20 breaths per minute, 4% had a temperature greater than 38 degrees C, and 25% had an abnormality on auscultation. Antibiotic prescribing was more common in the presence of abnormal chest signs (odds ratio = 8.71, 95% confidence interval = 3.69-20.61) or discoloured sputum (OR = 2.67, 95% CI = 1.57-4.56). Ten days after consultation, 58% of patients were still coughing and 29% had not returned to normal activities. CONCLUSION: Abnormal physical signs at presentation do not explain the high rates of antibiotic prescribing nor do they predict persisting cough and functional impairment at 10 days. Reconsultation for the same symptoms within a month is common and is strongly related to persisting cough, but not abnormalities at presentation.

Anti-Bacterial Agents↗

PubMed2004

[Use of drugs to treat respiratory tract infections in the community].

OBJECTIVE: This study describes the utilization of drugs to treat respiratory tract infections in a community setting. The description of antimicrobial and non-antimicrobial drugs use is important to design interventions aimed at improving treatment strategies for these common illnesses. METHODS: In a population-based cross-sectional study, 6145 individuals living in an urban area in southern Brazil were inquired about the use of drugs for the treatment of respiratory tract infections in the 30 days previous to the interview. The Pearson chi-square test was used for statistical analyses. RESULTS: The global prevalence of respiratory infections treated with drugs was 6.3%. The prevalence was higher for children under 4 years of age (18%) and lower for the elderly (3%; p<0.001). Fifty-nine percent of the individuals used antimicrobials to treat respiratory infections. "Sore throat" was the main clinical condition associated with drug use (41%). Amoxicilin was the antimicrobial drug most frequently used (38%), while non-steroidal anti-inflamatory drugs were the most frequent among the non-antimicrobial drugs (27%). CONCLUSIONS: Antimicrobials were used in nearly 60% of the respiratory tract infections treated with some drug, even though they are mostly viral in their origin. The indiscriminate use of these drugs not only raises the costs of treatments, but may also lead to the emergence of bacterial resistance against the antimicrobials.

Adolescent↗

PubMed1975

A theory of predicting respiratory tract deposition of inhaled particles in man.

The respiratory tract deposition of inhaled aerosol particles is due to three principal mechanisms: inertia impaction, Brownian diffusion and gravitational settling. A theory is developed to predict the particle deposition and its distribution in human respiratory tract for any breathing condition. A convection-diffusion equation for the particle concentration with a particle-loss term is used to describe the transport and deposition of particles. In this equation, an apparent diffusion coeffcient due to the velocity nonuniformities in the lung is introduced and is found to be the dominant diffusion mechanism. Expressions for deposition by various mechanisms in dead-space airways and alveolated airways are alo derived. The governing equation is solved numerically with Weibel's lung model A. The airway dimensions, however, are scaled to account for the average lung volume. The total depositions in the lung for particle sizes ranging from 0.2 micron to to 3.0 micron are computed for various steady breathing conditions. The results agree well with recent measurements using bis(2-ethylhexyl) sebacate particles and are less than the previous theoretical predictions. The regional depositions as well as the detailed deposition profiles along the airways are also calculated and discussed.

Aerosols↗

PubMed1984

Metabolism of a nasal carcinogen, phenacetin, in the mucosa of the upper respiratory tract.

The metabolism of [ethyl-14C]phenacetin in the rat and rabbit respiratory tract was studied. As shown by whole-body autoradiography, a selective binding of radioactivity occurred in the mucosa of the rat respiratory tract 5 min after an i.v. injection of [ethyl-14C]phenacetin. Microautoradiography showed that tissue-bound radioactivity was present in the epithelium of the nasal and tracheo-bronchial mucosa and in subepithelial glands in the olfactory mucosa. In vitro experiments showed that the mucosa of the rat and rabbit respiratory tract had a marked ability to metabolize [ethyl-14C]phenacetin, as determined by 14CO2 formation and binding of radioactivity to the mucosa. The results indicate that in situ metabolism of phenacetin in the nasal mucosa may play a role in the pathogenesis of phenacetin-induced tumours in the nasal region of rats.

Animals↗

PubMed1993

[Clinical studies of ofloxacin 300 mg once a day administration in chronic respiratory tract infections].

Forty patients with chronic respiratory infections were randomly assigned to 2 groups to compare the effect of once daily administration of 300 mg each and 3 times daily administration of 600 mg each of ofloxacin (OFLX). Twenty patients were administered with 300 mg OFLX a day and 18 cases received 600 mg. The number of underlying diseases in the 300 mg group was greater than that in the 600 mg group. The ratios of general amelioration of clinical symptoms were 80.0% in the 300 mg group and 88.9% in the 600 mg group. For bacteriological effects, the eradication rate was 80.0% in the 300 mg group and it was 84.6% in the 600 mg. The incidence of side effects in the 300 mg group was 0% and that of the 600 mg group was 5.6% (1 patient) but the symptom was mild. The incidence of abnormal laboratory test results was 15.0% in the 300 mg group and it was 11.2% in the 600 mg group, but all of these abnormalities were slight and transient. The safety rates in the 300 mg and the 600 mg groups were 95.0% and 94.4%, respectively. Efficacy rates in the 300 mg and the 600 mg groups were 80.0% and 88.9%, respectively. There was no statistically significant difference in all the results between the 2 treatment groups, and the both treatments were highly effective. From the above results, we consider that once daily administration of 300 mg is a useful therapy in respiratory tract infections.

Adult↗

PubMed2002

Styrene respiratory tract toxicity and mouse lung tumors are mediated by CYP2F-generated metabolites.

Mice are particularly sensitive to respiratory tract toxicity following styrene exposure. Inhalation of styrene by mice results in cytotoxicity in terminal bronchioles, followed by increased incidence of bronchioloalveolar tumors, as well as degeneration and atrophy of nasal olfactory epithelium. In rats, no effects on terminal bronchioles are seen, but effects in the nasal olfactory epithelium do occur, although to a lesser degree and from higher exposure concentrations. In addition, cytotoxicity and tumor formation are not related to blood levels of styrene or styrene oxide (SO) as measured in chronic studies. Whole-body metabolism studies have indicated major differences in styrene metabolism between rats and mice. The major differences are 4- to 10-fold more ring-oxidation and phenylacetaldehyde pathways in mice compared to rats. The data indicate that local metabolism of styrene is responsible for cytotoxicity in the respiratory tract. Cytotoxicity is seen in tissues that are high in CYP2F P450 isoforms. These tissues have been demonstrated to produce a high ratio of R-SO compared to S-SO (at least 2.4 : 1). In other rat tissues the ratio is less than 1, while in mouse liver the ratio is about 1.1. Inhibition of CYP2F with 5-phenyl-1-pentyne prevents the styrene-induced cytotoxicity in mouse terminal bronchioles and nasal olfactory epithelium. R-SO has been shown to be more toxic to mouse terminal bronchioles than S-SO. In addition, 4-vinylphenol (ring oxidation of styrene) has been shown to be highly toxic to mouse terminal bronchioles and is also metabolized by CYP2F. In human nasal and lung tissues, styrene metabolism to SO is below the limit of detection in nearly all samples, and the most active sample of lung was approximately 100-fold less active than mouse lung tissue. We conclude that styrene respiratory tract toxicity in mice and rats, including mouse lung tumors, are mediated by CYP2F-generated metabolites. The PBPK model predicts that humans do not generate sufficient levels of these metabolites in the terminal bronchioles to reach a toxic level. Therefore, the postulated mode of action for these effects indicates that respiratory tract effects in rodents are not relevant for human risk assessment.

Animals↗

PubMed2005

Antimicrobial treatment of lower respiratory tract infections in the hospital setting.

Respiratory tract infections (RTIs) that may require hospitalization include acute exacerbations of chronic bronchitis (AECB), community-acquired pneumonia (CAP), and hospital-acquired pneumonia (HAP), which includes ventilator-associated pneumonia (VAP). Healthcare-associated pneumonia (HCAP) is treated similar to HAP and may be considered with HAP. For CAP requiring hospitalization, the current guidelines for the treatments of RTIs generally recommend either a beta-lactam and macrolide combination or a fluoroquinolone. The respiratory fluoroquinolones (levofloxacin, gatifloxacin, moxifloxacin, and gemifloxacin) are excellent antibiotics due to high levels of susceptibility among gram-negative, gram-positive, and atypical pathogens. The fluoroquinolones are active against > 98% of Streptococcus pneumoniae, including penicillin-resistant strains. Fluoroquinolones are also recommended for AECB requiring hospitalization. Evidence from clinical trials suggests that levofloxacin monotherapy is as efficacious as combination ceftriaxone-erythromycin therapy in the treatment of patients hospitalized with CAP. For early-onset HAP, VAP, and HCAP without the risk of multidrug resistance, ceftriaxone, ampicillin-sulbactam, ertapenem, or one of the fluoroquinolones is recommended. High-dose, short-course therapy regimens may offer improved treatment due to higher drug concentrations, more rapid killing, increased adherence, and the potential to reduce development of resistance. Recent studies have shown that short-course therapy with levofloxacin, azithromycin, or telithromycin in patients with CAP was effective, safe, and tolerable and may control the rate of resistance.

Anti-Bacterial Agents↗

PubMed1978

Localized amyloidosis of the lower respiratory tract.

Amyloidosis limited to the lower respiratory tract is a relatively rare condition. Three new patients are reported, and the pertinent literature is reviewed. The available information is discussed with regard to clinical forms, diagnostic methods, therapy, and clinical course. Tracheobronchial deposition is the most frequent form of localized amyloidosis; it affects relatively younger persons and often gives rise to symptoms of airway obstruction. Bronchoscopy, although carrying a risk of bleeding, is the procedure of choice diagnostically and therapeutically. Single or multiple pulmonary nodules are usually discovered as an incidental roentgenographic finding, and surgical resection (for suspected malignancy) has resulted in cure in all cases. On rare occasions, amyloid may be deposited diffusely in the pulmonary parenchyma, leading to death from respiratory insufficiency.

Adrenal Cortex Hormones↗

PubMed1992

Herpesvirus infection of the respiratory tract in patients with alcoholic hepatitis.

Respiratory herpesvirus infections have rarely been described in alcoholics. We report four cases of severe respiratory herpesvirus infections in patients with alcoholic liver disease. Two were related to Herpes Simplex Virus and two to Cytomegalovirus. Both chronic alcoholism and severe liver disease induce immunosuppression, which might account for these unusual herpesvirus infections of the respiratory tract. These cases suggest that infections with herpesviruses should be considered in patients with alcoholic liver disease and pulmonary or tracheobronchial disease unresponsive to standard antibiotic therapy. Bronchoscopy, viral culture, and serological tests appear warranted, particularly given the existence of specific therapy.

Adult↗

PubMed1986

Respiratory tract disease in systemic lupus erythematosus.

Respiratory tract involvement is common in adults with systemic lupus erythematosus (SLE). Although SLE in children usually follows a more severe course than in adults, there are few reports on pulmonary disease and lung function in children with SLE. We performed lung function tests and chest x ray examinations in eight children with SLE (mean age 11.1 years), three of whom presented with pulmonary symptoms. A high prevalence of lung involvement was found, including interstitial or localised infiltrations, pleural effusion, a restrictive impairment of lung function, and dysfunction of the diaphragm. Three patients required artificial ventilation. Two main mechanisms of ventilatory impairment seem to occur in children with SLE: firstly, acute interstitial pneumonia, which rapidly improves on treatment with steroids, and, secondly, restriction of lung volume, mainly due to respiratory muscle weakness.

Acute Disease↗

PubMed1993

Penicillamine-induced changes in elastic tissue of the upper respiratory tract.

We describe a patient who developed upper respiratory tract symptoms following long-term treatment of Wilson's disease with penicillamine. These symptoms were attributed to areas of pharyngeal thickening and were treated with a laser. Histological examination of the lesions showed proliferations of abnormal elastic fibres similar to those previously described at other sites, especially the skin, in patients receiving penicillamine. This drug impairs the maturation and reduces the stability of elastic fibres and although elastic tissue throughout the body is affected, we are aware of no previous reports of penicillamine-induced changes presenting with upper respiratory tract symptoms.

Back↗

PubMed1999

[Successful total laryngectomy in three cases with severe motor and intellectual disabilities syndrome for the management of repetitive lower respiratory tract infections].

Total laryngectomy was successfully performed for the management of repetitive lower respiratory tract infections in three cases with severe motor and intellectual disabilities syndrome. The patients were thirteen, ten and nine years of age and had cerebral palsy, mental retardation and epilepsy which resulted from neonatal asphyxia and seizures. To treat repetitive lower respiratory tract infections, the patients underwent the operation at the age of nine years and a month, seven years and six months, and six years and eleven months, respectively. Postoperatively, the respiratory tract infections were remarkably reduced for two to four years. Total laryngectomy is one of the best methods for the prevention of aspiration pneumonia, because it separates trachea and esophagus completely. The operation is indicated for children with influx of saliva into trachea and gastroesophageal reflux. The family should recognize that this operation causes permanent loss of voice and speech. The bronchoscopy, upper gastrointestinal tract barium studies and esophageal pH monitoring should be performed before the operation. Our cases fulfilled all of these indications. Laryngectomy should be considered as an effective method of respiratory management for cases of severe motor and intellectual disabilities syndrome, although its application should be carefully examined from the point of improvement of quality of life for patients.

Adolescent↗

PubMed2004

The course of C-reactive protein response in untreated upper respiratory tract infection.

BACKGROUND: High C-reactive protein (CRP) values are frequently found in patients with bacterial respiratory infection, and CRP testing has been shown to be useful in differentiating pneumonia from other respiratory infections. Raised CRP values may also be found in viral respiratory infection, and as a result there is a risk that antibiotics may be wrongly prescribed. AIMS: To describe the course of the CRP response during untreated upper respiratory tract infections and associations between the development of CRP values, erythrocyte sedimentation rate (ESR) and respiratory symptoms. DESIGN OF STUDY: Prospective study. SETTING: Seven general practices in northern Norway. METHOD: Patients with upper respiratory tract infection aged 16 years or over, who were not treated with antibiotics and who had been ill for no more than 3 days, were recruited. Microbiological examinations were undertaken, together with measurements of CRP, ESR and recording of symptoms daily during the first week of illness and on days 10, 14 and 21. RESULTS: An aetiological agent was established in 23 of the 41 included subjects. These were: influenza A, influenza B, rhinovirus, and other agents. Among the 15 patients examined on both the second and the third day of illness, the median CRP value increased from 7-10 mg/l, and the mean value was from 19-24 mg/l between day 2 and day 3. Peak CRP values were reached on days 2 to 4. Higher CRP values were found in those infected with influenza A and B than in the other subjects (P <0.001). A CRP value >10 mg/l was found in 26 subjects during the first 7 days, compared to five subjects after 1 week. Evidence of a secondary infection with group A streptococci was found in two of these five subjects. The development of the symptoms of sore throat, fatigue, clamminess, and pain from muscles and joints followed a similar course as the CRP response, while stuffy nose, cough, sputum production, and dyspnoea tended to persist after the CRP values had approached the normal range. CONCLUSION: A moderately elevated CRP value (10-60 mg/l) is a common finding in viral upper respiratory tract infection, with a peak during days 2-4 of illness. Moderately elevated CRP values cannot support a diagnosis of bacterial infection when the illness has lasted less than 7 days, but may indicate a complication of viral infection after a week.

Adolescent↗